1)Holding a pair of dumbbells lie Flat on your back on a Bench with your feet on the floor.
2)Raise dumbbells straight over your shoulder with arms straight. Then bend arms at elbow to about 90 degrees. Elbows should be shoulder width or slightly less apart. This is your starting position.
3)Now perform 5(or number of your choice) dumbbell triceps extensions with one arm as you hold the other arm locked with the elbow bent at 90 degrees. After you have done (5) reps with one arm, perform the the same with the opposite arm while hold the last arm locked at 90 degrees. I like to perform 3 sets of 5 reps on each arm.