How to repair damaged DVD, CD and Blu Ray discs 

I've been asked quite a few times how I manage to clean my discs up and here's proof that even a battered Xbox 360 disc can by resurrected back from the dead.
P.s. this is NOT a paid advert and I earn diddly squat from making stuff like this - I'm just hoping this helps a few sellers / buyers and takes some of those completely rotten discs out of circulation.