I heard about numerous stupid fixes for such thing ( tooth pastes ) and **** like that , I had a Nokia n9 laying around so I tried like 10 home made recipes for thise and nothing worked , get used to it pal.
The way not to scratch your screen again is : if you have oil build ups clean them don't leave them alone. if you have dirt (specially grains of sand) don't wipe them directly blow on them and clean them in a one motion.
use a microfiber cloth (Kind like what you use for glasses.)
Sorry to disappoint you man ...