As much as possible, keep the group riding together . If you are just a bit behind the group, work a little harder to catch up and get back in the draft. If you are just slightly ahead of the group, drop your pace a bit so that you fall back towards the group. At the start of the ride, listen to the objectives of the ride and planned pacing , as described by the ride leader. Respect the plan by riding at the appropriate pace at the appropriate time, so that the group keeps it overall cohesion.
Most rides begin with a more mellow warm-up segment.
Be sure to stay with or behind the group leader during this segment even if you consider the pace too easy.