When I first learned to masturbate, I did it in the bathtub by sliding one hand down the length of my erection while making special contact with the ring just under my glans and then following it with the other hand. I just kept alternating hands and it provided almost constant stimulation to my most sensitive part. Years later I also started using just my right hand with more intense pressure focusing on the aforementioned ring. Often I use the left hand to fondle my testicles at the same time. I usually revert back to my two-handed method to build to and hang on the edge before finally allowing myself to ejaculate.