I have to say jelqing has worked well for me. Not only have I gotten length, though disappointed little girth, when I am totally relaxed after wearing briefs, my penis head is surrounded by extra skin, a psuedo-foreskin. That was an eye opening for me that this thing really works. Went from 5.5 to 6.5 within a few months.
As stated by previous posters, consistency and firm but not pain producing workouts. I generally did a 300 jelq routine, 5-6 times a week. Prior to the session I warmed up using a face towel. Run it under hot water- best described as warm to hot to the touch, temperature like those towels you might get after a long flight. I wrap my semi with the towel and let the heat warm up the shaft and the fat pad area. Generally 8-10 min. Its very relaxing.
I think this warm up is an important prep that cannot be emphasized enough. At each 100 count I repeat the towel routine.
I also did stretching exercises prior to jelqing. stretching to the left, right up and down.
I stopped for a few years and now have decided I want to hit 7 and beyond, will see where it takes me.