You will need a power buffer or power polisher/grinder for this, u can always get a harbor freight grinder and fine the adaptors to fit the bonnets. Anyways
clean/wash lights then…dry then
dip 800 grit sand paper and 1000 grit sand paper in a bucket of water after 10 minutes, wet sand the lights with ur 800 grit sand paper making sure that the sand paper and light are always wet, sand in one direction only. As you are doing this, u will notice the yellow/white residual fall off .do this for a good 7-10 mintues,, when you feel you are done. Get a dry towel and dry the light, u will noticed it hazed up and appears to be worse then what you had, don’t worry, then comes the 3M rubbing compound, rub it on the light,,,,wait about 10 min to haze and dry,,,then with ur power polisher start polishing the wax away. do not let it spin too fast or it can burn the plasic headlight. And make sure the polisher is always moving, don’t hold it in the same spot cus it will burn the plastic ,Wait 5 mins and repeat the same process with th 1000 grit sand paper. At the end if your not happy with your results u should repeat the steps…if you have really yellow headlights u might want to go with 600 grit sandpaper,…after you are happy with ur result…finish the headlight with a 3m glaze/wax this pretty much will protect and give it its luster back.
Don’t attempt to do the polishing my hand because it will not work, also those kits and waxs that are sold at auto part chain stores dont really work you wont get the results you are looking for with those, get 3M brand, if you don’t want to spend that much money get a professionally style wax/compound from online or a auto detailing store.
Also u might want to watch a how to video on youtube and try it on a car u don’t car about, before you do your own car.