hey, i'm 13, and here's the plan I used, which works great for me, but everyone is different. I have Hoist home gym, can't remember which model. On the poster that comes with it, it lists different exercises for the different muscles, i.e. posterior deltoids, anterior deltoids, obliques, biceps, triceps, etc..... I pick an exercise for each muscle and do 15 reps of it, at a weight that seems very easy to me. Then i increase the weight, so that after doing 10 reps, i'm about dead. I do this until I've worked every muscle. O, yes, one of the most important parts. I run 10 minutes on a treadmill before i "work out". At the rate i run, it's about 10 minutes for .85 miles, which is slow, but the point of it is to increase your heart rate and warm up your body correctly before you work your individual muscles. Then after i work out, i run 5 minutes at the same rate, but after I'm done jogging, i walk for two minutes as a "cool down". I do this every Tuesday, Thursday, and Saturday...hope it helped