fitboy,
Welcome to the gym!
Don't do the routine twice in one day, you're liable to overtrain. Check out our article on
physiological indicators that affect growth, it will help you avoid overtraining. You may even want to do the routine 1 on, 2 off for the first 2 weeks. The penis needs rest to grow, and you will probably gain just as much as you would doing the routine 2 on, 1 off.