At least three nail polish colours (try to pick ones that you like and that look pretty together)
Old throw away plastic tub, smallish (no bigger than 4 inches across)
nail polish remover
something to marbleize (anything small and water safe)
straw or wooden stick
Drop drips of nail polish into the water. It will float! Put the dots on top on one another and randomize the colours as you go. You have to work pretty quickly, the polish dries fast. You will need ten to twenty drips, they will spread out as you add more.
Take a stick or a straw and pull the colours out toward the edge of the dish. Swirl them a bit but not too much. If you over do it, it just looks muddy.
Dip the item into a pattern you like. Before you pull it up out of the water, clear the way by pulling any extra surface polish out of the way.
The finished fake nail. You can re-dip stuff to make more complicated patterns, or remove the polish with nail polish remover if it doesn't look the way you want it too.