Exercise your pelvic floor. You may not be able to build up the penis itself through exercise, but if you strengthen your pelvic floor your body will be better able to hold blood in your penis. The pelvic floor presses on the vein that keeps blood from leaving the penis during erections. You can strengthen your pelvic floor using Kegel exercises. A trial conducted in Britain concluded that men who performed Kegel exercises experienced better sexual function than those who made other lifestyle changes but didn't perform the exercises.
4 - Use a moisturizer on the penis before the exercises and it is preferred not to use soap and shampoo as these materials will lead to redness and irritation of the penis skin . If it stays for a long period of time, in addition to dry skin, and the occurrence of cracks, it is preferred to use the Intensive Care Vaseline instead of the ordinary Vaseline as it can stay on the skin for long period of time without irritating or damaging the skin of the penis.