Tip #2: Set logical rules and consequences.
Keep the goal of learning in mind and make sure students know why the rules are what they are: “We walk instead of running in the hallway because we want to make sure that everyone is safe.” And fit the consequence to the crime: If a student makes a mess of the art supplies, the logical consequence is to clean it up. Arbitrary punishments like losing recess, or something else unrelated to the offense, teach students that you are mean and trying to force a power struggle.