The best classrooms have established a culture for themselves.
This is not an accident.
This culture stresses and rewards the ideals of the teacher, as shown to the students. The culture has to be- and this is key- absolutely authentic for the teacher. It has to be real. It has to be genuine.
Be unabashed. Be bold. Be a dork. And do it every day, with a smile, and with no patience whatsoever for anything less than enthusiasm.
Just getting by will be the death of the culture of your classroom.