Now for this. I use my mouse for a few things; clicking, dragging, opening files and folders, but once I am in an application, my mouse is really just an expensive paperweight, keeping order over my Costco and Grocery Outlet receipts. Yes, I am a devotee of Keyboard Shortcuts. Although these links have more than you can learn in one viewing, even if you memorize a few (like Command-N for a new Finder window and Command-Shift-N for a new folder), your workflow will go smoother and your wrist will thank you.
Check this out, this is Apple's list of Mac OSX:
And this is one by nice guy Dan Rodney:
And of course, each program has it's own. Veteran users of Photoshop, Aperture, FInale and Sibelius use the mouse less and less.
You can also add your own in each program as well is in the OS through the keyboard pane of System Preferences. The possibilities are endless! Of course, so are the possibilities for conflicts between applications. So sometimes, you have to head over to that keyboard pane and reset the shortcuts to the default. But it is SO worth the trouble.
And I have not even talked about the Keyboard Viewer and Character Viewer. All in time, for sure.
Next time, the magic of the Option key, my fave!
Here's a bit of bling (ALT is the same as the Option Key):