Erect bends at the base can help, Always do bends cautiously though. You can use horse440's but that will limit gains above you base hold area. You can do hanging , have seen several posts stating girth increases at the base. Another you can do in reach up through your sac and pinch the shaft. 80% erect. Grab the head and part of your shaft and compress it tightly. This will change the internal pressure as a Uli would only you are farther down below the pelvic bone. This can help some. Experiment, try different things. You'll stumble onto what will work for you.
You can do a sort of "modified Horse squeeze". Clamp off at the base with your ok grip...finger and thumb right against the bone. Then using most or all of the other hand and grip and squeeze the glans and front of the penis. Should focus most of the pressure at the base if done properly.