Component Systems sells a powder paint air brush . If you don't have one you could try the tap method by dipping a brush in powder then tap it and let the powder float into the cavity . If yyou try this method follow the above instructions only put the mold on a griddle or something so the temp will remain 350 until your mold is coated . If the mold has a lot of crevices like a ringed worm or something like that I wouldn't bother It's to hard to coat those smoothly.