What happens if the ball hits me or my hand?

After the serve, if the ball touches you or anything you're wearing or carrying, it's a fault against you. The exceptions are your paddle and your paddle hand below the wrist while it's holding the paddle (Rule 10.C.3).

Related paddle rules:

• You must be holding the paddle when you hit the ball. You may use one or two hands and switch hands at any time (Rule 12.B).
• You can't catch or carry the ball on the paddle (Rule 12.C).
• Hitting the ball more than once is only legal if it's one continuous stroke in a single direction by one player (Rule 10.D).
• Completely missing the ball isn't a fault; the ball stays live (Rule 10.E).