To select a layer on the Canvas, simply click on it. When you do this, you’ll see selection handles appear around that layer.
You can also select a layer in the Layer List by clicking on its name.
Tip: If you can’t see the selection handles, check they’re enabled by heading to View > Canvas > Show Layer Selection.
Selecting multiple layers
To select multiple layers, select your first layer, hold ⇧ and click on another. You can also hold ⇧ and click on a layer you’ve already selected to remove it from the selection.
Alternatively, click-and-drag from an empty area on the Canvas to select any layers within your selection area.
Holding ⌥ while you click-and-drag will only select layers and Artboards that are completely within your selection area.
Holding ⌘ while you click-and-drag, will pierce through groups in your selection (or remove currently selected layers). It won’t select Artboards.
Holding ⌘⇧ while you click-and-drag will remove any currently selected layers from your selection and add any unselected layers within your selection area.
You can also select all of the layers within a specific Artboard, by selecting the Artboard itself and choosing Edit > Select > Select All in Artboard from the menu bar.
Selecting overlapping layers
You can hold ⌥ to select the second layer underneath your pointer instead of the top one.
If you have more than two layers overlapping, you can Control-click, choose Pick Layer from the shortcut menu and select the layer you want.
Measuring layers against the Canvas and other layers
To measure the distance between different layers on the Canvas, select the first layer, then hold ⌥ and hover over the layer you want to measure against. To measure against a layer that’s inside a group, you’ll need to hold ⌘ as well.
If you’re measuring the distance to a text layer, holding ⌥ will measure to the text’s bounding box. Holding Ctrl will measure to the text’s baseline (from the bottom) or cap height (from the top).
You can change the colors of the measuring guides via the Canvas tab in Preferences.