I use Mother's Polish with a fine microfiber cloth to do the polishing, use a second cloth to finish getting the residue off on my Naval Brass Cartel. After that I use Turtle Wax paste waxing compound to help bring the shine out further, this also adds a layer of wax against the salt and oil of your sweat, lasts about a week at most, though it does make the mod slick and slippery as heck. Without Ceramic Coating the mod, there really isn't much you can do to stop the patina of copper mods, and being brass is copper and tin alloy, suffers from copper's tendency to patina quickly as well especially when constantly exposed to salt and sweat oils all day long from your hands.
