Paint the wall that will have the galaxy black
Use the 2" brush and white primer to map out the galaxy
After the white is on, mix a little black with blue and purple. Sponge this on by patting lightly-
-and rub in to give the illusion of dark clouds. Do this mainly on the darker, black areas
Put curves on the white to make it appear cloud like, unless you are painting a less cloud like galaxy.
Put paint (white or metallic- your choice) on the toothbrush. Rub your finger on the bristles and flinging the paint on to make stars
You should have this
Use another sponge to apply lighter colors, blending is not needed unless prefured