1. Select All Shortcut

1. Select All Shortcut

If you are like me and work with multiple artboards a lot, you need to be aware that the default Select All shortcut, Cmd/Ctrl + A selects all objects on all artboards. Cmd/Ctrl + Option/Alt + A selects only the objects on the active artboard. If you prefer to have this the opposite around, you can change this via Edit > Keyboard Shortcuts..., choose Menu Commands go to the Select menu to switch the shortcuts.

2. Group Selection Tool

2. Group Selection Tool

The Group Selection Tool is a tool that a lot of people —including myself— often overlook to use, but it's actually a very helpful, and time-saving one. Especially if you're working with grouped objects nested within another group. The 1st click will select just a single object of the group, click again and you select the group of the object, click again and now you select the group that the grouped object is part of, and so on. Try it out!