Pranking is a great way to bond with your friends. Unless you do it wrong, then it is a great way to ruin your friendship. It's very fine line between joyous prank and cruelty. A bad prank is just bullying. A good prank shows everyone that you're thoughtful. A surprise party is essentially a prank. It's the nicest prank you could pull. Shaving someone's head in their sleep is not a nice prank. It's just mutilating someone.
There's a rule that I like to start with. It's only a prank if you're not actually doing the thing to a person. For example, if you pretend you're a masked killer and scare your friend, that's a prank. If you actually stab them, that's not a prank. I've seen Youtube videos where a white guy will call a black person the N word and call that a prank. That's not a prank. That's you calling someone the N word. Don't be that person.