Deselect in Photoshop?

I wanted to quickly write up a tutorial for how to deselect in Photoshop. This is by no means an exhaustive tutorial that covers all the tips and tricks, but it will get you through 95% of the work you might need to do. The first thing that I want to mention is that there are two main ways to deselect in Photoshop: by going to Select->Deselect, or by changing your foreground color and then painting with black on your selection.