Building muscle mass isn't so easy to achieve and it wouldn't come very fast as you probably think. It is not achievable, not without using steroids. Building lean muscle takes some time and you can't gain 50 pounds of muscle mass in one month, you can only gain body weight like that, and that means mostly body fat.  First, you have to remember that if you want to build muscle you have to get stronger. To get stronger you have to lift heavier weights in the range of 6 - 10 reps and you will also get bigger. For totally new lifters I advise that they should first start with bodyweight exercises and gain some strength and muscle growth before they start lifting heavy weights. Pull Ups and Dips are very good Muscle Mass Builders, those exercises should always be in your workout routine.  Also, besides getting stronger, to gain more muscle mass you have to eat more healthy foods every day, you have to consume a lot of proteins, carbs, and fats. For tips on...