jelqing works, but you gotta keep doing it or you will loose what you gained.
i once watched this show about sex, and there was this dude sitting in this chair naked, he had a huge dick... i didnt really watch the whole show, i was just flippin thru the channels... anyways, he was talking about how he got such a huge dick and he said that he basically just squeezes it, stretches it, pulls it, jelqs it, etc, etc.. he said sometimes he will spend 2 hours in a day just doing shit like this.. he said whatever forces more blood into your cock and makes your dick pumped and bigger feeling/looking will eventually stay with you... sorta like when you work out, right after you are pumped and look bigger, eventually you look like that all the time (ofcourse we dont notice it because we are constantly doing this and gaining very slowly)...
whatever you do, make sure you do lots of kegals, cause you want to be able to continue to get hard erections... without kegals, you may grow an inch, but you wont be able to get as hard.