How do you get a good pant job with rattle cans?

By good, I dont mean proffesional. I just want something to not be blotched up, what prep should I take for a plastic yoyo? or a metal yoyo? I’m just going to do an undercoat then do the old glue overtop then do black trick.

Generally surface prep is the key on plastic or metal. Then do multiple light coats rather than a heavy coat which will no doubt run. It has to be wet enough, but not too wet. If it’s not wet enough you get a textured, mottled finish. You really have to experiment a bit on a practice piece to see what is enough or too much.