Using the right mouse button
Clip Gallery has many functions on menus that you access by using the right mouse button (right-click):
Right-clicking a clip or category will bring up a menu, and you can then select the function you want. If you have your mouse set up to be used by your left hand, then you can access that menu by clicking your secondary button, which in that case would be your left mouse button.
Tip
See also:
Shortcut keys