Wash the headlights with soap and water
Dry the headlights completely
Mask the paint around the headlights with tape
Apply toothpaste, baking soda paste, or a headlight cleaner
Rub the lens with a microfiber cloth in circular motions
Rinse the headlight and wipe it clean
Use wet sandpaper if the haze is heavy, starting with a fine grit
Keep the surface wet while sanding
Move to a finer grit for a smoother finish
Apply a plastic polish and buff the lens
Wipe off any residue
Apply a UV sealant or protective coating
Repeat as needed for stubborn oxidation