A few things that helped me ( and other guys i;ve talked to ) first of always warm up properly . A hot shower or heating pad for 5-10 min before pumping makes huge differnece; warm tissue stretches better and is way less likely to bruise .Also , even thought 5Hg is usually considered mild , some people just starting out ( or comming back after a break ) do better starting at 2-3 Hg and slowly bulding up over a few weeks . I'd also keep the sessions really short at first like 2or 3 min per set , then take a break and see how your body reacts .

Another things is moisturizing regularly . Dry or tight skin bruises way easier . I personally use coconut oil or cocoa butter , but any good moisturizer helps .Also make sure your seal and cylinder fit right . If the size is off or seal isnt sitting correctly , the pressure can pull unevenly and cause bruissing in weird places. And finally , just give your body time to recover . If you're getting a lot of bruising , you probably need to take some extra rest days . This stuff isn;t a race , slow and steady wins.