Say you have 40 files in a Finder folder and want to select 30 of them, spread out (non-continuous). You can:
- Click on each of the 30 holding (Command).
- Select all 40 (A), then hold and click on the 10 you want to deselect.
Or do something like this:
Just select the files you want to leave out and then, holding, clicking and dragging them out. The Finder will automatically select what is deselected, and deselect what is selected.
Of course, the tip works best in the view of icons like the one in the GIF above. 😉
(via Macworld UK)