An effective study group ideally should have 3-4 members, no more than 5 max. Your group should meet at least once a week and you should decide how long sessions should be. All members should make a serious commitment to show up and to do the required preparation prior to any group meeting. If you show up unprepared it will impact how effective that session is for the whole group. Choose a group leader. This person would be responsible for keeping the group on track and on task within each session so that no one gets frustrated with pace or with time being wasted on other things not relevant to mastering the course material. This person should also send out a reminder email on weekly time/location info, plus any session info that’s relevant.
Students distinct roles within their groups, one student is responsible for initiating and sustaining communication with the rest of the group, another with coordinating schedules and organizing meetings, another with recording ideas generated and decisions made at meetings, and a fourth with keeping the group on task and cracking the whip when deadlines are approaching. The instructor rotates students through these roles, so that they each get practice performing each function.
A technique that fosters collaboration is a consensus decision making framework. Consensus builds group cohesion by incorporating everyone's opinion in the group. Rather than approaching consensus from an "I can live with it"…