What class rules are essential to a positive teaching/learning experience?

I have found that my classroom management has improved since I have broken everything down in to steps and have clear rules and expectations posted around the room. Because I am working in an art room, if I don't have clear expectations and rules about the cleanup on top of the actual lesson, it can throw off other classes and my day as well. I have learned from my cooperating teacher that when I want something done right I have to enforce that rule and can't let anything slide in the classroom. This does not only apply for clean up, but also applies during demonstrations, work time, and the amount of effort and quality that is expected of students by myself, my coop, and the district. Clear and concise classroom rules are essential to a positive teaching and learning experience. I have found out along the way during my weeks here that I need to repeat and reiterate every last detail, even ones that I may think that they would already know. I have learned that I need to be above and beyond prepared and organized both physically in my room but also mentally so that all rules are being followed. I need to actively be present in the classroom to make sure that my classroom management is being followed and that their work is following the expectations of higher positions than my own.