I've generally started with a piece of about 80 grit paper and the. Move to 100 grit. From there, I'll tune it with various papers ranting to 320 grit. Might even hit it with a piece of scotch brite. Be warned though, I've ruined a couple of pots figuring this out. Listen to the masters above. They've got more experience than I've got and will lead you in the right direction.