Fighting on the flag is also extremely important. It does no good to be in a 5min stand off at BS if an enemy is just going to cap the flag while you are not looking. Do you best to AoE all enemies near the flag and prevent a cap.
Run together as a team and avoid having to res and run by your self. Call out a flag your going to attack and meet with other players to accomplish your goal.
AB is pretty simple if you play as a team and follow those steps^^