When I was starting out with polishing, this was sound advice I got from those in the know (Jimble):
"The rule of thumb is to start with the least abrasive pad/compound combo, inspect and step up the pad with the least abrasive compound until you decide that it's not enough then step up the compound on the least abrasive pad and so on.."
+1 on Poorboys super swirl remover. Comes in increasing degrees of abrasiveness SSR1, SSR2, SSR2.5 and SSR3 - take your pick!