Here's how it works: Pick out the design you want, and Easy Ink will send it to you. As you would with any other temporary tattoo, you place the sticker onto dry skin and wait; within a few hours the ink will darken and you can peel it off to reveal your new body art. But here's the difference between this one and the ones you'd rip out of Tiger Beat when you were little: This formula is waterproof, and will stay put for two weeks.