Get your supplies! Use whatever colour paint/nail polish you can find!
You'll mainly need dark colours!
Begin to sponge on a black base coat.
Now begin to add spots of other colours, such as purple, blue, gold and silver. Be creative, and look at a picture of the galaxy for inspiration!
Use a toothpick to paint tiny, gold/silver spots
Go over the spots to make them more pronounced.
Paint the finished product with glittery nail polish. Done!