When you have finished the beginners routine which will condition your dick, look into the stickies on the Devices Forum and check out pumping. I attribute pumping to increasing my girth by about 1/2 inch, though it took about two years. Pumping also provides an immediate though temporary (several hours) gain in girth.
Make sure you're fully conditioned with JP90 and feel free to stick with it even longer or add to it if you are gaining with it. Concentrate on the quality of the stress that you are trying to put on your penis during the various exercises and let your penis dictate how many reps and days are right for you. More is not necessarily better.
After you're well-conditioned, there are many options for a girth focused routine. I don't have the privacy for devices, but a few months primarily with squeezing, followed by flaccid bends and supra slammers really triggered some girth gains. I could then see and feel my penis expand during the course of the workout and started seeing measurable gains over a month.