1. Stick the hat except the white sign with adhesive tape, and pay attention to the cloth in the arc position, otherwise the paint will flow in.
2. After all of them are glued, you can see the part where only the white logo is exposed and then sprayed with black paint. After a few separate sprays, the white logo can be dyed black.
When the paint is completely dry, tear off those tapes so that the hat will have a black mark.