Most all of the poker sites (including Party Poker) have play money tables for you to learn the ropes. You can create an account without having to deposit money, so there’s no risk involved while you’re learning.

A note to remember however, is that free play should be used to learn the mechanics of the game, but not necessarily perfect your strategy. Most players in free games will play like complete maniacs since it’s not real money, so your poker experience in a play money game will be very different than a real money game.