Superfine steel wool is an option (tape off the pickup magnets - that stuff always seems to find them.) Other options include wet sanding with fine grade sandpapers or micro-mesh finishing pads (stew mac sells those.) Synthetic steel wools (garnet or grey) work pretty much like standard steel wool, they don't make a mess like regular steel wool, but also do not cut as aggressively. My own favorite is a product caller Mirlon from Mirka, it comes in a three pack of medium, fine, and superfine. Leave the medium alone and start with fine then switch to superfine, it's a bit more spendy than other synthetic abrasive pads, but gives a really fine cut and cuts a bit more aggressively than many of the other products.