How Do You Discipline A One Year Old?

If its even possible at such a young age. My daughter is almost a year old. and she likes to get into trouble. lol like all kids at that age. and when she does something , like hits another baby or something, I will slap her lightly on the hand, and say "No Hit". but now I don't think that works anymore, cuz every time i do that, she starts laughing hysterically at me, like we are playing a game. She's too young to reason with, or put on time outs, so is there really any way to discipline at such a young age? thanks.