To that end, I wanted to share a few tips from the League of American Bicylist course on Group Riding.
A good cyclist always looks or scans behind before moving laterally to a different position on the roadway or in the group. You are looking for cars as well as other cyclists.Use Signals
Cyclists use hand and verbal signals to communicate with members of the group and with other traffic. Within a close group, it makes sense to use verbal signals such as "Right turn!" "Slowing!" or "Stopping!" rather than hand signals, but riders at the front and rear of the group should use hand signals as well for the benefit of other road users.Give Warnings
When riding in close formation, each rider must feel a responsibility toward the riders behind. You must warn of road hazards and of changes in your direction or speed. The lead rider should announce turns and hazards well in advance so that members of the group have time toposition themselves properly and safely.Ride One or Two Across
Ride single or double file as appropriate to the roadway and traffic conditions. Double is always more fun. Nevertheless, as a courtesy, we are quick to single up when this will permit faster traffic to move by us more efficiently. "Car back!" is the signal to get into single file.Change Positions Correctly
Remember, when passing, always pass on the left saying "On your left!" Now don't scream this - startling a cyclist is never a good idea.
These are just a few of the excellent suggestions from the course for keeping safe and avoiding accidents. Any other suggestions?