Positive Failure enough weight to fail because its too heavy, but not because the muscle is tired but because it fails to have the power to lift a heavier weight. The is centered around an approach of at least 4 but no more than 6 reps.
Linear Progression: This is a complicated way of saying to make the weight just a bit heavier, each week. Over time, the muscle will grow.
Rest: workouts should only be about 3 days a week, and workouts need to be 30 minutes or less.
Food: eat clean all the time and you will grow. Eat like crap, look like crap.
Volume Sets: German volume training, instead of 10 sets of 10, its 5 sets of ten, or the last one may be 6-8 Combine that with linear progression and rest pauses. I had a client do this combo and gain 18lbs of muscle in a month.