I've seen a lot of interest in clamping as of late..... especially on a couple other PE forums. Sadly too many guys engage in exercises they aren't ready for, being convinced it's the Holy Grail to easy gains.
I've said this countless times ad nauseam.... Clamping is an ADVANCED PE exercise. It shouldn't be done by rookies (newbies). Let me define a rookie for you..... anyone who doesn't have a minimum of 6 months of dedicated PE training (Hand stretching - JP90, jelqing, and traditional weight hanging (quality vacuum based device).
It takes a significant amount of time to develop the tissue maturity and conditioning that will enable you to reap the benefits of clamping.
I can think of numerous examples of other physical disciplines that require time to develop the ability to engage in and perform at certain levels. Nobody skydives from 15000' ft altitudes starting off. Nobody starts off deep sea diving at 200' ft.
Engaging in clamping before you're adequately conditioned / prepared leads to ruptured blood vessels and potentially a hematoma.
My personal clamping routine was typically 3 sets of no more than 10 minutes. Between sets I would do moderately aggressive jelqs.
My ultimate goal was to gain uniform thickness / girth throughout my entire shaft length. Which I'm happy to say I was fairly successful at accomplishing. I would often include pumping with my clamp work, and follow up with 5-10 minutes with my LGH Jelq Roller.
Double clamping and using a wider clamp that provided more surface contact allowed me to use less clamp pressures.
A section of silicon sleeve or Girth Band under the clamp provides an extra measure of comfort and prevents the potential skin pinch.