Try opening and closing folders with the left and right arrow keys instead of double-clicking.
One of the best tricks for speeding up your computer work is to keep your hands on the keyboard, not the mouse.
It’s not a macho, anti-mouse thing, but a simple matter of efficient motion. Using the mouse or trackpad means moving your hands off the keyboard, locating the cursor, making your move, and then shifting your hands back to the keys. If you can skip these steps, things tend to go faster.
There’s no better example than navigating folders within Finder windows. You can select, open, and browse folders from the keyboard for greater speed and less multi-window clutter.
Test it out yourself: In Finder, open a new window by pressing Command-N. To view the folders in List view, press Command-2. (Command-1 lets you view by Icons, while Command-3 changes the view to Columns.)
In List or Columns view, choose a folder that contains several subfolders, and open it by pressing the right arrow key. You can move up and down between folders or documents by pressing the up and down arrow keys. Close folders (or navigate backwards, if you’re in Columns view) with the left arrow key.
When you’ve located the file you want, speed your work even more by opening it with Command-O instead of double-clicking. In most Mac applications, you can close the file again by typing Command-W.
Once you’re accustomed to navigating through folders and files with key commands, you may be surprised by how fast you can move around, mouse-free, on your Mac.