Ive developed my own system posted her on my Grampa Joe's Baby Needle
after you let your air brush work dry, get yourself a cheap walmart craft paint .. white with micro glitter, and apply it with a wet rag.. Go heavy when it dries it dries clear and the only thing you can see is the sparkle finish.. Ive yet to see a more realistic scale shimmer.. Hope that helps , ive seen some really crappy glitter jobs when guys try to mix it themselves,