Wash the headlights with soap and water
Dry the surface completely
Mask off the paint around the headlights with painter’s tape
Apply headlight cleaner or polishing compound
Rub the lens with a microfiber cloth or foam applicator in circular motions
For heavy oxidation, wet-sand with fine-grit sandpaper, starting with the lowest needed grit and moving to finer grits
Keep the lens and sandpaper wet while sanding
Wipe away residue and check the clarity
Repeat polishing if needed
Apply a UV protectant or headlight sealant
Let the sealant cure according to the product instructions
Clean the headlights regularly to help prevent fogging again