The more sets and reps you do, the more you can increase your endurance.
Your reps should range from 15 - 20, and your sets could be as high as 4 - 6 or more. Doing DROP SETS is a good idea, to keep the muscle under tension for a prolonged period.
Your REST time should be minimized, to put your muscles under stress.
CIRCUIT TRAINING is one of the best methods for working on endurance, because it requires you to do lots of exercises in little time.