2D Canvas Editor: Layers, Drawing & Vector Tools

The 2D editor gives you a Photoshop-style layer stack, raster painting, and a full vector pen/shape toolkit. Tools live in the tool row in the top bar, and the active tool's options in a panel down the left; the layers float in a stack on the right. The chat bar sits at the bottom, as on the board, and Tab collapses it. Under it a row of shortcut hints shows what the tool in your hand does. The X at the row's right end opens Settings → Keymap, where Show shortcut hints turns the hint rows off everywhere in the app, and back on. The media panel does not open from the right edge here, where the stack is: open it with Media in the top-right corner, and close it with its pin.

The 2D editor is its own section: the 2D Editor button (the paintbrush) on the left rail, just below the Board. It needs no board open — a document (a composite) belongs to your library, and opens from Home or the media panel with Open in 2D Editor, a double-click, or the Open button on its Home card — never in the image preview. Double-clicking a node zooms into node focus, which is a reading view, not the editor.

Opening & saving

There are three ways in:

• An image in your library: right-click it on Home, or open its ⋯ menu, and choose Open in 2D Editor. That starts a new composite from a copy of the image and opens it; the image itself stays as it is, and each time you do it starts another composite. It is offered on images you own.
• An image on the board: hover or select its node and click Edit in 2D Editor (the paintbrush) in the node toolbar. The rail switches to the 2D Editor, and Back to Board in the top bar returns you to the node.
• The start screen: click 2D Editor on the rail with nothing open. Like the board's, it shows your Recent documents on the left — click one to open it, or All documents for Composites on Home — and on the right everything for a new one: a name, a Size picker with the presets in two groups, Social (Square, Portrait 4:5, Story 9:16, X post, LinkedIn post, YouTube thumbnail, Pinterest pin) and Screen (Full HD, QHD, 4K UHD, Phone wallpaper), the width and height to type your own, 16 to 4096 pixels a side (the picker then reads Custom), and a background (white, black or transparent). Up to three settings decide where it lives besides your library: Place on board places it on the open board as a node (only while a board is open), Link to board files it with a board you pick in the list under the switch — any of your boards, the open one to begin with — and Folder puts it in one of your folders. A new document opens with an empty Layer 1, active and ready to paint, above the locked Background. Close document in the top bar saves the document, closes it and takes you to Composites on Home. New composite on Home saves and closes whatever the editor holds, then opens this start screen.

What the 2D editor has open stays open while you work elsewhere. Switch to the Board or Home and your changes are saved on the way out; click 2D Editor on the rail and you are back where you left off. It holds one image at a time, so opening a different one while another is open asks first: Save and open saves the current one, closes it and opens the new one, and Cancel leaves everything as it was. If that save fails, nothing is replaced and the dialog stays up. Switching away from the browser tab saves too, and closing it while a change is still unsaved makes the browser ask before it leaves.

There is no save command or save key: the editor saves by itself a few seconds after you stop editing, at most about half a minute apart while you keep painting, when you switch away from the browser tab, and when you leave. To keep a flat copy as a new image in your library, open the ⋮ menu at the end of the toolbar and choose Save as new image; it does not add a node to the board, and nothing on the keyboard does it. Right-click the canvas for Save Layer as Image, which saves the active layer on its own, named after the layer.

Press F to frame what you are working on: the selected layers, or the whole image when nothing is selected. Hold R and drag to turn the view. On a touchscreen, put two fingers on the canvas and move them like a sheet of paper: they pan, spread or pinch to zoom, and twist to turn the view, all at once; one finger still paints. A Mac trackpad does the same in Safari with trackpad mode on — Chrome and Firefox do not report a trackpad twist, so there a pinch only zooms. Let go within a few degrees of straight or a quarter turn and the view settles onto it; any other angle stays where you left it. Right-click the canvas and choose Reset View to re-fit the whole image, whatever is selected, and turn the view straight again.

Layer stack

The layers float as a column of cards over the right side of the canvas, top layer on top, centred top to bottom. A card is the layer's thumbnail; a path layer reads Path. Names are kept but not shown — a card's name is its tooltip — and there is no rename. Click a card to make it the active layer. A stack taller than the window scrolls, fading out at both ends; with a pen, which has no wheel, hover near the stack's top or bottom edge and it scrolls that way, faster the closer you are to the edge. Selecting a layer, or adding one, makes it the only selected layer, so the card that lights up is always the one T transforms.

Hover a card for its controls:

• Visibility — the eye, top left. Press it and drag across other cards to flip them all. A hidden layer shows its eye without a hover.
• Lock — the lock, top right. A locked layer's pixels, position, look and place in the stack can't change, and it can't be deleted: painting, erasing, Delete, Blur, Adjust, Flip, transforms and dragging all refuse it, and say which lock is in the way. What only reads the layer or makes something new still works — Duplicate, Save as PNG, Remove Background, Layerize, selecting its pixels. Locking a folder locks its whole subtree; its layers show an inherited lock you can only release at the folder. Background opens locked, and a locked layer shows its lock without a hover.
• Delete — the bin, bottom right, or Delete/Backspace with the layer active and no selection. Background, a locked layer, a folder holding a locked layer, and the last layer can't be deleted. With several layers selected, the locked ones are skipped.
• Blend mode and Opacity — two pills that slide out to the left of a card once the pointer rests on it for a moment, so sweeping across the stack does not open them on every card. Opacity has no slider: drag across the number. A layer below 100% opacity shows its percentage in the card's bottom-left corner. Blend modes are Normal, Multiply, Screen, Overlay; a folder's start at Pass Through.

Soft images. An image layer shown larger than its own pixels allow carries a small grey note in its card's bottom-left corner saying how many times it is enlarged, 2.4× for example, once that is past 1.5: a 1024-pixel image stretched across a 4K document, or a photo scaled up with the transform handles. It is a note, not a warning — point at it for what it means. It goes away when the layer is scaled back down or replaced with a larger image; painting on the layer, duplicating it, copying from it and undoing keep it, and it survives closing and reopening the document. Merging keeps the softest layer's value.

Hover the seam under a card for a white pill of Duplicate, + (a new empty layer there) and — only when the card sits between two layers that can merge — Merge down. The seam above the topmost card has Duplicate (a copy of the top layer, on top) and + (a new layer on top), with the + over the card's centre. A document holds at most 50 layers.

Drag a card to restack it; drop it onto a folder to put it inside. A layer being generated appears as a card with a spinner at the top of the stack.

Folders. A folder is a line down the right of its layers under its name, with − / + on the line beside the name to close and open it. Click the name or the line to select the folder; right-click either for the folder's menu. Double-click the name to rename the folder: Enter or clicking away keeps the new name, Escape keeps the old one, and the rename is one undo step. A closed folder is one card previewing its top layers — one, two side by side, or four in a grid. An open folder has no card, so close it to reach its own eye, lock, blend mode and opacity. Folders nest, each level stepped further in. Make one by selecting layers and choosing Group Layers from the right-click menu, or Ctrl/Cmd+G. A closed folder's card shows a row of colour dots above its blend mode: rose, peach, butter, mint, sky or lavender (or none) tints the folder's name, its − / + and its line.

Hiding and showing (H hides the selected layers, Shift+H hides the others, Alt+H shows them all), locking, opacity and blend mode are each one undo step.

Multi-select layers with Ctrl/Cmd+Shift+click (toggle) or Shift+click (range); Ctrl/Cmd+click a card selects that layer's pixels, as Cmd+click on a thumbnail does in Photoshop, or drag a box with the Select tool. One box serves both: it selects every layer whose picture it touches on the canvas and every layer whose card it touches in the stack, so a box started on the canvas and dragged over the cards selects those cards. Start it in the space around the cards rather than on one to box the stack from there. The selection follows the box as you drag. Shift adds to the selection and Alt takes away.

Layer right-click menu

Right-click a card for: Duplicate Layer, Save as PNG, Template (see Templates), Remove Background (image layers), Group Layers (when 2+ selected), Merge Group / Ungroup / Select Children (on groups), one merge row, and Delete Layer / Delete Group & Contents. The merge row reads Merge Layers when 2+ layers are selected and you right-clicked one of them, and merges exactly those; otherwise it reads Merge Down and merges the clicked layer onto the one below. Ctrl/Cmd+E (or Ctrl/Cmd+Shift+E) makes the same choice. Merge Group turns everything inside a folder into one layer in the folder's place, with the folder's name, visibility and opacity; layers hidden inside it are dropped, and a folder of paths only becomes one editable path layer.

Remove Background runs the AI cut-out on that layer alone and adds the result as a new layer, leaving the original in place — so it works on a locked layer too. It appears only on an image layer you can currently see — a path layer, a group or a hidden layer does not offer it. See Image AI Tools for the model and cost.

Templates

A template is a piece of a picture you keep to stamp onto any canvas again: a rim, a car's glasshouse, a figure you sketch with often. Templates live only in the 2D editor. They are not in your library, your folders or your tags, and you find them through the Template row, which unfolds Save as Template and Load Template… in place.

• Save a layer: right-click an image layer's card, or the canvas, and choose Template → Save as Template (on the canvas, Save Layer as Template, for the active layer). It keeps the layer's own pixels, trimmed to what they show.
• Save a selection: draw a selection, right-click the canvas and choose Template → Save Selection as Template. It keeps what the selection covers on the active layer, trimmed the same way.
• Load one: choose Template → Load Template… from either menu. The dialog shows your templates in a grid, newest first; type to search them by name. Click one and it sticks to the cursor, see-through, at the size it was saved; click the canvas and it lands there as a new layer, centred on the cursor, in one undo step. Esc or a right-click puts it away. Hold Space to move the view while you aim.

A template is named after the layer it came from. In the dialog, double-click a name, or right-click a template, to rename it; Delete there removes it for good.

Raster vs vector layers

Two layer kinds coexist in the same stack:

• Raster layers hold pixels — painted with Brush/Eraser/Bucket, or generated images.
• Vector (path) layers hold editable Bézier paths — created by the Pen, Pencil and Shape tools, and re-editable any time with the pen sub-tools.

Merging keeps vectors editable when it can: path+path combines into one editable path layer. Every other pair rasterizes — raster+raster, and a mixed path+raster merge, bake into pixels on the raster layer below. Groups don't merge.

Brush & Eraser (B / E)

To paint: select Brush (B) and drag on a raster layer. Eraser (E) removes pixels the same way. Set the paint color with the color swatch in the toolbar. A stroke follows a smooth curve through every position the pen or mouse reports, so a fast stroke curves instead of breaking into straight pieces; the last short stretch is drawn when you lift.

Paint mixes like real paint. Where a stroke crosses paint, the two blend the way pigments do, not the way light does: a half-opaque yellow over blue turns green rather than grey, and over red it turns orange. How much the new paint wins is its opacity and flow. Painting a colour over itself leaves it exactly as it was, however many times you go over it. Paint mixes with everything you see under the brush: the paint already on the layer, and the visible layers below it. Yellow painted on a new empty layer over a blue photo turns green there too. Only the layer you are painting on changes; the layers below are never touched, so the stroke on its own layer holds the mixed colour it showed when you painted it, and moving or hiding the layers below afterwards doesn't re-mix it. The Eraser removes paint as before. Mix like paint, a switch at the bottom of the colour picker, turns this off: each stroke then lays its colour over what is there with ordinary blending, and mixes with nothing below. The switch is remembered, and a stroke keeps the setting it started with.

Brush settings: right-click the Brush or Eraser toolbar button. The Eraser has settings of its own: size, hardness, pressure and the rest are set separately from the Brush's, and nothing done on the Brush — a slider, a preset, a recent brush — changes the Eraser. The popover has:

• Size, Opacity, Flow, Hardness — side by side along the top, within reach while painting. Drag sideways across one to change it, with the mouse or a pen; Size grows faster the further you drag, so a small brush still moves a pixel at a time.
• Tip Shape — Roundness, Angle, Grain (on a textured brush: Texture — Grain alone)
• Dynamics — Spacing, Scatter, Size Jitter, Rot. Jitter (Rot. Jitter on round-tip brushes only), Groove (Brush only)
• Pressure affects (pen tablets): Size, Opacity, Both, or Off

Brush presets: open the brush settings popover to pick a preset. Presets and recent brushes are the Brush's; the Eraser keeps just its own last settings. The presets are Hard Round, Soft Round, Airbrush, Ink Pen (round-tip brushes) and Ballpoint, Pencil, Charcoal, Crayon, Marker, Spray (textured brushes):

• Pencil, Charcoal, Crayon lay a cloud of fine grains across the stroke on a paper texture that stays put under the brush, so hatching over the same patch leaves the same specks of paper showing. A light touch catches only the paper's high spots and a hard press fills it in; Grain sets how much paper shows at all.
• Ballpoint behaves like a ballpoint on soft paper. Its range is wide: a light touch draws a faint hairline, a hard press a dark line about ten times as wide. The paper shows through it the way it does through Pencil, fixed to the layer: a light line skips the paper's low spots and a hard one fills them; Grain sets how much. Each stroke presses a dent into the layer, and a new stroke running close beside an old one slips into its dent, so going over a line makes it bolder instead of doubling it. The pull is partial and fades at the edge of the dent, so a hand that means to leave leaves, and a line that crosses an old one goes straight over it. A line pressed hard, or gone over twice, pulls more. Groove sets how strong the pull is, on any brush; 0 turns it off. The dents last while the editor is open, and undo and the Eraser leave them, as they would on paper.
• Marker lays translucent ink, darker where strokes cross, with a little pooling where the stroke starts and ends.
• Spray lays a disc of fine droplets, densest at the middle.
• Every preset and recent brush is shown as one stamp of its tip, not by name: point at one for its name and size. The stamp is the brush's own tip, drawn at full flow and the size of the tile, so it shows the tip's shape, softness and grain; the Size and Flow sliders say how big it is and how much each dab lays. The big preview beside the presets is the brush in hand, drawn the same way.

While painting, press [ / ] to shrink/grow brush size, or drag with Control+Alt held (horizontal = size, vertical = hardness), as in Photoshop. On a Mac that is Control+Option (⌃⌥) — the Control key, not ⌘: holding ⌘ cancels it. Alt/Option + right mouse button drag does the same.

Bezier control

With the Brush in hand, tick Bezier control (hint "bend lines") in the options panel on the left. Each line you draw then keeps handles on it, so you can bend it after you lift the pen. Drag a handle and the line passes through the pointer; the other handles stay where they are. The line stays your own stroke, wobble and all: bending moves it, it does not redraw it as a clean curve.

Where the handles go depends on the shape you drew:

• A line or a single arc gets a handle at each end and one in between. An S-curve gets two in between.
• A line with sharp corners (an L, a zigzag, a triangle, a square) gets one handle on each corner, shared by both sides, so dragging it moves both. Straight pieces get no handle in between; curved pieces get one or two. A closed shape has one handle per corner.
• A closed loop that follows an ellipse is held as that ellipse, with four handles. Drag a long-axis end to stretch and turn the ellipse around the opposite end. Drag either short-axis handle to set its width; the other one moves with it.

The handles stay until the line lands: drawing the next line, picking another tool (the Eraser too), or turning Bezier control off lands it. Undo reopens a landed line. Say you bend a line, then draw a second one: the first undo takes the second line away, the next gives the first line its handles back, and the one after that takes it away. That only works while the Brush with Bezier control is still in hand; otherwise undo just removes the line.

Symmetry and circles (O)

Symmetry (hint "mirror as you draw") is a checkbox in the options panel of every tool that draws: the Brush, the Eraser, Shapes, the Pen and the Pencil. Turn it on and everything you draw is copied across a guide drawn on the canvas. The brush and the eraser copy every dab as it lands; the pen, the pencil and the shapes copy the finished path. With it on, the panel shows:

• Axis: Vertical, Horizontal, Both or Radial.
• Segments (Radial only): how many copies go round the centre, the one you draw included, from 2 to 32. Mirror (hint "kaleidoscope") also mirrors each segment.
• Angle: turns the guide around its centre, 0 to 359°.
• Circles (hint "O"): see below.
• Center on canvas: puts the centre back in the middle. To move it anywhere else, drag the dot on the canvas.
• Rim preview (hint "3D"): see below.

The guide's lines invert what is under them, so they show on a white canvas as well as a dark one. The guide's settings last for the session.

Circles draws circles round the symmetry centre. Click and you get one whole circle round the centre, through the point you clicked. With the Brush or the Eraser, hold and drag in or out to sweep more: another full circle lands at every brush spacing as you move, at the pen pressure you have there. The sweep is one stroke and one undo step. The pen, the pencil and the shapes lay a circle path instead. Press O to turn Circles on: it turns the symmetry guide on with it, and from a tool that cannot draw circles it picks the Brush. Press O again to turn Circles off.

Rim preview

Tick Rim preview under the symmetry rows to see your sketch as a wheel rim in 3D, in a small view in the options panel. The sketch inside a circle around the symmetry centre (dashed on the canvas) is projected onto a dish, inside a tyre drawn as an outline in the brush colour. Drag the view to turn it. It updates when you finish a stroke, undo, or change the layers.

• Standard, Sporty and Rugged each set the tyre and a matching dish shape.
• Under them, a side view of the dish, hub to lip, sets its shape. Click a point to pick it and drag it. A picked middle point shows Point radius (how round that corner is; 0 is sharp) and Remove point. Double-click empty space to add a point, and double-click a point to remove it.
• Radius sets the rim's diameter as a share of the canvas's shorter side.
• Shading (hint "matte, lit") lights the dish. It is off at first, so the sketch shows in its own colours.
• Add to canvas adds the view as you see it now as a new layer named Rim render, centred on the rim, in one undo step. Rim render layers are left out of the sketch the dish shows.

Bucket Fill (G)

To flood-fill: select Paint Bucket (G) and click. It fills with the current brush color. Tolerance in its options panel (0–255, default 32) sets how far a colour may differ from the clicked one and still fill.

Tool settings stay as you left them: the Brush and the Eraser, the bucket's tolerance, the pencil's feel, the style the next path or shape is drawn in, Auto-Select, the marquee the Lasso button stands for, and the pen's sub-tool. They carry over from one document to the next, and your account keeps them, so they are the same the next time you sign in, on any device.

Pen & Pencil (P)

Pen (P) and Pencil (N) are separate buttons in the toolbar.

• Pen (P) — click to place anchor points; drag to pull Bézier handles. Each path becomes its own vector layer.
• Pencil (N) — drag a freehand line; on release it's fitted to a clean editable path. Its options panel (left rail) has Stabilize (live input smoothing) and Smooth (finished-line fit).

When a vector tool is active, a second sub-bar appears with the pen sub-tools and the Shape/Corner tools.

Pen sub-tools (vector sub-bar)

• Move / Direct Select (V) — select and move anchors and handles. This is the base edit mode; clicking an active sub-tool returns here.
• Add Anchor (+) — add an anchor point to a path.
• Delete Anchor (−) — remove an anchor point.
• Scissors (C) — cut a path into separate sub-paths.
• Bend — bow a straight segment into a curve.

Shape tool (U)

To draw a primitive: open the Shapes split button in the toolbar (U), pick Rectangle, Line, Ellipse, or Polygon from its chevron menu, then drag on the canvas. For Polygon, set the side count with the −/+ stepper in the dropdown. Shapes are vector paths.

Corner tool (fillet radius)

To round corners: pick the Corner tool in the vector sub-bar. Its top-left panel has two modes:

• All — the Radius slider live-rounds every corner on the selected path layer(s). Select more layers to round them together.
• Individual — drag each corner's widget on the canvas.

Vector path styling

With a path layer selected (Pen, Shape, or Direct Select V), the left rail's options panel exposes styling. Writes apply live to the path:

• Stroke — toggle + color + Width.
• Fill — toggle + color.
• Taper — thin the stroke toward the ends, with an Amount slider.
• Parallel — fan offset copies of the stroke: Distance, Count (interpolated lines), and Offset X/Y.
• Sketch — a hand-drawn look: a Style dropdown (Sketchy / Pencil / Rough) over Roughness, Wobble, Passes and Grain, all shown at once.
• Texture — procedural stroke grain: Pencil / Charcoal / Chalk, with Scale and Strength. It is part of Sketch, sitting under it, and turns off with it.

Flatten (Pen panel) bakes parallel copies and rounded corners into plain editable paths.

Selection tool & marquee

• Select (V) — the default arrow: click layers, move and free-transform their content. Clicking a layer fits it to its pixels, so a small painted layer moves and transforms as its painting, not as a box the size of the canvas.
• Lasso (L) — a split button; the chevron picks Polygonal Lasso, Freehand Lasso, Rectangular Marquee, or Elliptical Marquee to make a pixel selection. Pressing L again switches between the polygonal and the freehand lasso. With a selection over a layer, T lifts the selected pixels and transforms them, as in Photoshop; Enter, a double-click outside the box, or Escape puts them back into the layer.

Selection shortcuts: Ctrl/Cmd+A select all, Ctrl/Cmd+D deselect, Ctrl/Cmd+I invert. With a selection active, Ctrl/Cmd+J = layer via copy, Ctrl/Cmd+Shift+J = layer via cut (without a selection, Ctrl/Cmd+J duplicates the layer), and Delete/Backspace clears the selected pixels on the active layer. While the selection itself is being transformed, Enter keeps the change and Esc puts it back.

To add detail to one part of the picture: draw a selection, right-click it and choose Upscale selection under AI (its price shows when you point at it). It sends what the canvas shows inside the selection to Nano Banana 2.1 Edit, asking it to sharpen lines, remove blur and add texture detail without changing what is shown. The model draws only certain shapes, so the selection first snaps to the nearest one (16:9, 4:3, 1:1 and so on) and you see it change; it grows around its centre so everything you selected stays inside. The whole result comes back as a new layer, Upscaled selection, scaled into exactly that box — nothing is cut out of it. It asks for about twice the selection's size, from 0.5K up to 4K, which is what moves the price.

Right-click with a selection for its menu, in sections: Selection (Transform, Invert, and Modify, which unfolds the Expand, Shrink and Smooth sliders), Pixels (Delete, Layer via Copy/Cut, Copy Merged, Save as Image, and Template), AI (Remove Objects, Upscale selection) and Filters (Blur... and Adjust..., see Filters). The sliders add up: all three apply together to the selection the menu opened on, in that order, and dragging one back to zero undoes just its part.

Filters: Blur and Adjust

Both work on the active image layer, and only inside the selection when there is one. Right-click the canvas and choose Blur... or Adjust...: on the default menu they come after Distort and Warp, and on a selection's menu they sit under Filters. They are not on a layer card's menu. The panel opens where you clicked, and the layer shows the change while you set it. Apply keeps it as one undo step. Cancel, or a click outside the panel, leaves the layer as it was. A locked layer refuses both.

• Blur: Gaussian (even), Motion (streaked in one direction, with an Angle) or Radial (spun around the layer's middle), with a Strength from 1 to 100 pixels.
• Adjust: light, curves and colour in one panel:
  • Light: Exposure (−3 to +3), Brightness, Contrast, Highlights and Shadows (−100 to +100).
  • Curves: a curve for RGB, Red, Green or Blue. Click the line to add a point; drag a point out, or double-click it, to remove it. Reset curve puts the shown curve back.
  • Color: Temperature, Tint, Hue (−180° to +180°), Saturation and Vibrance, and the switches Black & White and Invert.
  • Reset puts everything back. Apply stays greyed out until something has changed.

Segment tool (S) — AI object selection

To select an object by clicking it: pick AI object selection (S) and click on the subject of the active layer; the AI returns a mask you can turn into a new content layer (Segment, or Object 1, Object 2… for several) or a mask layer. It reads the active layer as it sits in the picture, so it works on any image layer, not only the background; a folder is refused. Useful for isolating a subject before further editing.

AI object selection costs no credits. Each person can run it 200 times a day; once those are used, another becomes available every few minutes, and the message says how long.

Path Warp (W) — puppet warp

To bend an image along a path: pick Path Warp (W). In the top-left panel, Pick one or more paths and one target Layer (click on the canvas or a card in the layer stack), then Morph. While warping, drag the path's anchors and handles to deform the image; the Influence slider sizes the warp's reach. Apply (Enter) bakes it into the layer; Esc steps back. Undo (Ctrl+Z) reverts one morph step within the live session.

Tip: draw a guide path with the Pen (P) first, then warp the image along it.

Merge, group & transform

• Merge Layers — select 2+ same-kind layers, then Ctrl/Cmd+E or the right-click menu. Only the selected layers have to be unlocked; a locked layer below them does not stop it.
• Merge Down — with one layer selected, Ctrl/Cmd+E (active layer onto the one below), or the right-click menu.
• Group — Ctrl/Cmd+G (selected layers into a folder). Ungroup — Ctrl/Cmd+Shift+G.
• Free Transform — press T to scale/rotate/move the active layer's content. Selecting a layer draws no box over the picture: its row lights in the layer stack, and the Select tool moves it by dragging on the canvas. The box with its handles is drawn only in Free Transform. Scaling and turning both go around the crosshair in the box (the pivot), with no key held; Shift keeps the proportions, and dragging the crosshair moves the point they go around. Enter applies the transform and the layer stays selected.
• Alt-drag to duplicate — hold Alt/Option and drag a layer (or, in Free Transform, its box) to drag out a copy. The copy is selected.

History

Undo — Ctrl/Cmd+Z. Redo — Ctrl/Cmd+Shift+Z. Drags, slider sweeps, and arrow-key nudges each collapse into a single undo step.

History keeps the last 30 steps. On a very large image it keeps fewer, so the history fits in memory: an image up to 2048×2048 keeps all 30, and the step you just took can always be undone.

Keyboard shortcuts

Press Shift+? for the shortcuts window, which lists these under 2D Editor. On a Mac, Ctrl in this table is Cmd and Alt is Option.