Communicate what constitutes good behavior to students and lead by example. Tell your kindergartners that it is up to each of them to behave respectfully toward one another and to play nicely. Use positive reinforcement for good behavior. If you praise a student for helping another child, for instance, he will begin to see the positive consequences of helping others.
Give students a chance to correct their own behavior if they do something wrong. Institute a system of warnings that allows children to know when they are crossing a line. For example, create a color-coded system where yellow means a warning and red means they have misbehaved. If a student looks agitated and about to hit another child, say the word "yellow" to her. Take the student aside and ask her what other things she might do to express her dissatisfaction. Give her a chance to make a positive choice instead of acting out.
Discipline by showing kindergartners the direct consequences of their actions and implementing a loss of privileges. If a student defaces another student's work with crayons, for example, forbid that student from using the drawing station for a set amount of time. Explain to a student very clearly why what he did was wrong and how it affected another student. Have the student take responsibility for his actions by apologizing.