Idk if rotating wheels goes under begainers corner or wheels so since Jacob L put it in beginners corner I'll put something in here to have it in both beginners corner and wheel discussion.
Here's some info on keeping sets of wheels similar sizes: the wheels that wear the most are the wheels with the most weight on them. That should be front heel for healsides, front toe for toesides. Keeping in mind coning- you should always try to put the biggest wheels up front.
Typical rotations should be in a X. I generally do 2 X then a side to side and repeat.
Wheels should be ideally be rotated whenever their is a visible difference between them. On slow wearing wheels that is probably every session or so, and fast wearing dumpers that could be every run (you probably will be too lazy to on dumpers and that's ok.)