Typically when we discuss "toning" or "shaping," what we're really talking about is muscular endurance. For this type of training, perform 12-15 repetitions per set, keeping your rest periods between sets very short (between thirty and ninety seconds). For beginners, start out with just one set, working your way up to 3-5 sets per exercise. As long as you continually incorporate the principle of progressive resistance, it isn't entirely necessary to include multiple exercises per bodypart. Therefore, if you perform three sets of biceps curls using 10-pound dumbbells, and are able to successfully complete 16 reps on your first set, 14 on your second and 14 on your third, then you need to increase the weight, decrease your rest between sets and/or include a couple of extra sets to your workout (i.e. the weight is too easy for what you're trying to accomplish). The next time you perform this workout, try using the next highest set of dumbbells, such as 12.5-pounders. If you find that you can only get 10 reps on your third set, stick with this weight until you can successfully complete all sets within your 12-15-rep range. When you successfully complete this goal, increase the weight again.