[Almighty So]

For full headlights, sand around 4-500 rpm or by hand with the following:
1200
1500
1800
2000
By now your headlights should be pretty murky looking. You can start at a higher grit if the oxidation isn't too bad. The worse it is, the lower grit you'll need.
After this, hit it with a 3000 to really smooth it out.
Clear coat over and done.
Should look brand new unless you messed up.