Yep......what Hank said! I use a 12 " Dura-Block with paper folded in half the long way. Wear gloves and dip the block in a bucket of warm water (to clear the residue.......warm to be kind to your hands). I do start with 800w after 24 hours at 70f. Comes off very easy while the paint (or gelcoat) is green. Buff it out after a week or so.
Have fun,
JJ