Put water in a bowl, drop random colors of nail polish in and swirl with toothpick. put petroleum jelly on your fingers so the polish only sticks on nails not your fingers. Stick fingers in bowl, nail polish should float on top of water.
I'm trying to develop a bohemian look for asian girls (it's hard because most of us are short and petite instead of tall and lanky making it difficult to wear such clothes). I think I may have found some inspiration for this look in Tribal Aztec Nails