It is best to stand at a distance of three to five feet when disciplining another person, giving room to breath and respecting the other's right to his own space. That is sobering. At first it may be threatening, but think about it. Students react to poor teaching just the way you react to poor administration. Good rules are reasonable.
Good rules are enforceable.
After you have set up a good rule, there are two more rules for rules governing what you do to make them work for you. The fourth rule for rules is enforce the rule every time it is violated until the desired behavior is learned. After it is learned, it will not be a problem anymore. You can tell when people have learned to do the right thing because they do it all the time without any reminders. You can't enforce rules everytime they are violated if you have too many rules.