What i like to do for shoulders is start off with push press to fatigue the muscle i mean 12 to 15 reps for three to four sets then get down and blast them with dumbells sides front and finally upright rows to kick start them when i start to see no results is i do either standing or seated behind the neck press first real heavy and then drop all my reps in dumbells down between 6 and 8 reps and squeeze the muscle