Model the behaviors that you want to see in your students. A community circle is about the give and take of ideas and information in respectful manner. Have a signal that indicates quiet. When a student is speaking, give him your undivided attention. Your students will pick up on this behavior quickly in most cases, but if not, you can demonstrate with a student for the rest of the class. Be prepared to have practice meetings at first, to get the students used to the new concept and to build confidence. Often shy students will become comfortable enough to volunteer after a few circle sessions.
Most teachers set their community circles up in an actual circle, to designate its difference from regular class time. This prepares the students for the activity and makes it special. The circle shape emphases that right now, everyone is equal and can participate. Call on students or use a prop like a baton or stuffed animal to select turns for speaking; some teachers use alphabetical or seating order to give each student a turn. Older students may enjoy holding an election to choose a discussion leader and a secretary to take notes and keep track of the circle's decisions.
Most circles address common classroom issues like setting and following procedures, addressing student concerns and conflict resolution. This creates a safe space to discuss things like bullying or cheating and the repercussions of those behaviors. If there are no pressing issues involving rules, discipline, or mediation, you can do icebreaker topics that get conversation started, like a favorite TV show or places the students would like to visit. Icebreaker prompts help draw shy students out and make them feel more comfortable speaking in the group, so that when they need to air something important, it will be easier for them.
As every teacher knows, class time is a premium. Some teachers opt for short daily circle meetings, some have a meeting once a week. Teachers in middle and high schools who only have students for brief periods because of changing classes can make time for a class meeting by scheduling it once a month or once a semester.