K.I.S.S. :
Consider 5X5's for a start. Train no more than 3 times a week. Twice may even be better for you, not knowing your work/school plans. Have liquid balanced amino protein shakes between main meals (sip it...do not chug-a-lug it). Keep the calories up to at least 3,200 to 3,500 daily, with an eye on quality carbs. If not gaining as you wish, than jack up the calories to 4,000. Probably will not need much more than that if your metabolism is somewhat normal.
With the above 5X5's in mind, plan a full body workout for the first 6 to 8 weeks of training.
Pick one exercise per body part:
Legs: squats, front squat, leg press, BB Hack..Suggest the full squat
Back: BB row, chin, lat machine pulldown...Suggest BB Rows
Chest: bench, incline, dips (weighted)...Suggest Dips
Shoulder girdle: Military press, DB press (one arm at a time), Press Behind Neck...Suggest PBN
Throw in a 2 sets of tri/biceps if you ego demands...but really not needed. One set of abs after each workout. Never go to the point of complete failure. Easy on the cardio, if doing any.
So many guy's at this time of years seem to have the summer time blues when it comes to adding quick muscle mass. Good Luck.