While I certainly haven't tried every proposed method, I've been pumping more or less regularly for about 30 years. When I started, I was about 5 or 5.5 inches by about 4 inch girth. I'm now about 7.5 x 6.5 permanently. I likely could have done it in fewer years had I been more rigorous with my schedule ... when I started I did it just because I liked the way it felt, and perhaps more important, I had a buddy who loved it, too.