Naughty!

No, do not presume "it's pointless to start until I can do it right"; what is pointless is not to start in the first place, immediately.

Not sure what your work entails, but if any part of it is in relative privacy and involves only one hand, you can at least do the frænulum stretch. Exactly how you ask? Well, you should at some stage be able to identify where the frænulum ends in the foreskin as in this illustration, so that is where you grip to do the stretch.

I think you will find plenty of Web references for "flesh tunnels", but one company is selling them as a packaged set for this specific purpose. (Dodgy Web site though!)

I omitted to comment earlier, but it is disturbing to find a seventh grade "Bible class" teacher who clearly does not have an understanding of the Bible and apparently has not actually read it in any genuine depth. Still, that sort of thing happens, my own experiences with the Christian school as parent and advisor revealed a few problems also.