Ok I will tell you what worked for me adding girth.
After I did the newbie routine for around 3 months, I added pumping.
My routine consisted of pumping and some jelqing.
Once I added the pumping I began to add girth. I gained about 1/2 inch from this. It is permanent girth gains. I have gone for long periods without pumping, but the gains have stayed.
I followed the Thunders pumping for enlargement guidelines. If you follow those guidelines, pumping is very safe and gentle. (Clamping is much harsher and more potentially dangerous in my humble opinion)
10 to 12 minute sets. 3 to 4 sets per session. Come out of pump between sets and stroke to get a good hard on, then go back in the tube.
Do not pump higher than 5HG pressure. I had best results around 3.0HG or lower.
Read up in the pumpers forum when you get a chance:
Pumper’s Forum
This is a good article:
Vacuum Pumping 101