Selecting layers in Sketch is easy: you just click on the layer on the canvas. Once the layer is selected, you should see eight little handles; one in each corner and one on each edge.
Note: If you don’t see these handles but are sure you selected the layer, you may have accidentally hidden the Selection Handles. To toggle them, go to View › Canvas › Show Selection Handles in the menu.
Alternatively, you can use the layer list to select a layer. Clicking a layer’s name in the list will select it on the canvas:
Selecting Multiple layers
You can select multiple layers by holding down the shift (⇧) key on the keyboard. If you then click another layer it will preserve your original selection as well. If you hold ⇧ and click an already selected layer, it will be deselected.
Click + drag from an empty area of the canvas to select everything that fits in the rectangle. Again, if you have ⇧ or command (⌘) pressed, it will extend your selection or deselect any already selected objects.
If you hold down the alt-key (⌥) as well, it will only select layers that lie entirely within the bounds of the rectangle. Compare the images below. On the left: ⇧ and drag. Right: ⇧ ⌥ and drag.
To make it easy to select a layer that is buried under another layer, you can right-click and choose ‘Pick Layer’ from the menu. There you will see a list of every layer that is under your mouse:
Note: In Sketch 2.x this was accomplished by pressing ⌥ ⌘ and clicking. This has changed in Sketch 3.0 to right-clicking instead.
A convenient shorthand for this is the ⌥ key. When it is held down, Sketch will select the second layer under the mouse instead of the top-most one. If there are multiple layers overlapping and you want the third one then you’ll have to go through the contextual menu as described above, but in some cases this can be a very convenient trick.
Quickly Selecting Layers in Groups
Groups are a very convenient way of organizing content, and sort-of prevent layers from accidental edits; until you double-click it, the group is treated as one layer and its contents can’t be selected individually.
However, there are situations where you want to select a particular layer buried deep inside a hierarchy of groups. To save you lots of double-clicking while you go down deeper and deeper into the group hierarchy, you can instead hold down the ⌘ key and select that deeply buried layer straight away.
If you hold down the shift key as well you’ll be extending your selection, as described earlier.