There are two primary benefits to stretching before you work out. Stretching prevents soreness and also helps you to continue exercising. Stretching regularly will also broadens range of motion, which will facilitate your muscle-building efforts. Eat something both right before and after your workout. A snack that is high in protein and low in sugars or fats will keep your body properly fueled. As you gain more experience in increasing muscle mass, you should be more picky over carefully measuring out how much protein you are consuming and planning out meals with more focus.