Use consequences, not punishments. A consequence is something that is naturally caused by a behavior. For example, if you are obnoxious or threatening, you can't be around people for a little while. If you make a mess, you clean it up. If you leave my tool outside, I won't want to lend it to you next time you ask.
Children learn how to behave better from having natural consequences.
A punishment is something that is given by an angry adult for revenge. For example, if you do that one more time, you can't go to the park tomorrow. Stay in control. Everyone gets mad. The trick is to catch yourself when you're just starting to get upset or frustrated.