My question is why are you trying to gain the muscle? Going for a new position on the squad? And like Paul said give it TIME! Things that come quickly leave you just as quick… Check out Jim Wendler’s 5/3/1 program works on the basic’s Squat, Bench and Deadlift.
That which is measured improves. That which is measured and reported improves exponentially.. Translation track your sets/reps don’t walking into the fitness center to “workout” go into train! You have your day already laid out no guessing what will be done of the day..