The beard trimmer works for mowing down the forest. Stubble isn't that bad, it's the long hairs that you miss that will make you pay attention. Don't wait until the day to mow. clean it up a couple days ahead of time. Next day after you have a shower and washed all the trimmings away you can inspect and find the wild hairs you missed.
You don't stretch the cath over the hose. It goes into a barbed fitting. The most basic is a double barb that goes into the hose and the cath. Better is a quick connect. And trim a little off the tip of the cath, minimize the chance of a kink.
For getting it off. Everyone is a bit different but my best method is to pull laterally. It is amazing how much they will stretch. As it stretches the adheasive isn't as strong. Work it off little by little by pushing in as you stretch out and work your way around. If you practice at home, only do it once a day. Natural body oils tend to help in the release. That is if you can wait 4-6 hours after putting it on it will be better than if you take it off 15 minutes after putting it on. I typically pull it off before heading home, unless it was a really short dive or a canceled dive, then the extra hour to get home tends to help.