My big thing is respect. I just want my students to respect me enough to be attentive throughout my presentation and, in return, I'll respect their need for bathroom and social time. And remember people, punishment isn't the best way, reinforcement is. On sort of the same note, my cooperating teacher for 203 had great classroom management skills, or very effective at least. Give a few minutes, take a few minutes.
Kids are people too.
The best way to get your class to conform to the bells is to enforce such a policy form the very beginning. If you hold them after or use some other behavior management strategies from the very beginning, they will quickly learn that dismissing themselvs will not be toelrated. Is it possible, yes. It just depends on how far you are willing to go to make it happen. I would say that generally this is nearly impossible.