I think this is so true when it comes to classroom discipline. Setting the expectations at the beginning of the year is key to creating a classroom that runs smoothly and without too much conflict.
A few ways to do this:
1. Have your class rules clearly visible somewhere in the room. Refer to the list as you are reinforcing the rule.
2. Have a routine for everything. Kids thrive when they know what is expected of them and what comes next. Give them that security by having a fun little routine for getting in line, packing up their bags, turning in their work, getting ready for lunch, etc.
3. When you introduce a new rule, practice it over and over. Your kids will get a kick out of pretending that they are 'going crazy' and having you do the signal to quiet them down.
4. Give you students some say in what rules your class should have. Call a class meeting and talk about what new rules our class should have. You might be surprised what they come up with!
Here's a few classroom management ideas you might be interested in:
What are some ways you start the year off smoothly?