What you'll need:
*A large bin (at least 5" deep)
*Nail polish color of choice
Pour water into the bin until it is deep enough to cover the mug about 3/4 of the way to the top.
Quickly pour the nail polish onto the surface of the water. Depending on the age of the nail polish, it should spread out when it hits the surface. Blow on it to disperse clumps, or use a toothpick to swirl colors together.
Dip the mug in the water on top of the nail polish. It should adhere instantly. Set the mug on a paper towel to dry.
If you accidentally get nail polish inside the mug, simply wipe it away with a paper towel soaked in nail polish remover. You can also clean up your marbling this way to create the exact look desired!
For added protection, spray your mug with clear acrylic sealant.
Enjoy your unique marbled mugs!