When I first got into diving a dry suit I simply put it on and did a few dives in the quarry. Granted at the time I had a few years of dive experience under my belt and had purchased my suit used from a private party. After "trudging" my way through a few dives a good friend who is an experienced instructor made me an offer I couldn't refuse, he was willing to let me tag along on a dry suit class he was teaching for the bargain cost of a steak dinner and the c-card. I took him up on the offer simply because I had nothing better to do that weekend. While at that point I didn't learn much about diving a dry suit itself, it did teach me a great deal about fine tuning the dive experience, maintenance and care of the suit, and proper undergarments to use(I was using sweat pants and a fleece jacket at the time). What he also taught and the most value I got out of the class was learning about added accessories that simply make the experience amazing! I knew nothing about p-valves, dry gloves, or heated vests, and while I have yet to take advantage of the latter two I at least knew about them for future reference. So even though I knew how to dive a dry suit going into the class I definitely got my money's worth out of the course. So in closing....spend a few extra bucks and take the course, there are plenty of great instructors waiting to show you how to do it right!