Im a firm believer in rotating excercise. Example....If I do chest workouts with dumbells then the next week I will do barbells or machines. I try to work all the combinations as much as possible. This helps against the muscles becoming to accustomed 2 one workout, it also makes it more fun. I usually start some with form of lat pull downs, seated rows,. I do a wide and open grip on each. Bent over rows are great also. I do about 4 sets each excercise. If I see I am getting fatigued early then I cut it down to 3. I always start with a different excersise each week. Seated rows seem to be my best friend. Basically incorporate everything, do FAILURE sets, drop sets if necissary. Lift with god tempo and form. Get huge!