[lproven]

My #1 top tip:

Use a desktop PC, not a laptop, and unplug the mouse. Learn to navigate solely with the keyboard. This is perfectly doable, works very well on Windows and some Linux desktops, and it will give you a good appreciation and understanding of good vs. bad UI design -- because there are a thousand small things that aren't noticeable when pointing and clicking.

This doesn't mean just using the shell. Any competently-written GUI can be navigated by keyboard alone.

It'll make you faster, you'll learn a lot of "power user" shortcuts and things, and it makes you better at designing software that is accessible to users with sensory or motor disabilities.