Really though, how many days should I exercise, how many reps should be in a set, and how many sets should there be in a session? I am interested in the upper body and this time I will say that I am willing to be vain and go for mass.
There is no one correct routine as long as each muscle worked has adequate time to recover between exercise days.
That said, three sets of ten reps each is a great start for a beginner and 3-4 sets per exercise seems to be quite popular.
For building mass, I’ve read that heavier weights and fewer sets or reps with an emphasis on intensity is preferred (as opposed to lighter weights and more reps for a leaner, swimmer’s physique).
Take the reps slow instead of flying through them, focus on maintaining good form, and on the last rep in each set, try to hold for 5 seconds before bringing the weight back down.
Once you can easily hit 3 sets of 10 reps with little resistance, then it’s time to increase your weight to the point of no longer being able to hit 10 in the third set. Work your way slowly back to being able to hit all 10 in the third set, then increase the weight again.
I usually do four days, rest 1-2 days, and repeat. I do chest and triceps one day, upper back and biceps one day, legs and abs one day, shoulders one day. I am usually in and out of the gym in 30 minutes to an hour and a half. I get my cardio from outdoor walks when I can.
You’ll probably find a preferred style and schedule that works best for you. I recommend trying different routines until you find something optimal. Just start slow and focus on avoiding injury at first. Warmups like stretches are nice. Hydrate frequently and remember to breathe during each rep. Take adequate rest between sets (at least 30 seconds and up to several minutes, depending on how hard you’re pushing yourself).
Since you’re interested in upper body, I would recommend push-ups for your chest and triceps, and bicep curls. Side and front raises for shoulders, but being smaller muscles, you will want lighter weights for those. If you have access to a gym, any machines for upper body exercises should be used. Both free weights and machines are good and each have their strengths, so it’s good to mix it up and incorporate both into a routine if possible