I studied all the stuff. Memorized formulas, wrote out problems, internalized the whole works. Knew the workbook back and forth, all the facts in the back of the workbook, etc. I did that for over 7 months maybe 15-30 mins. a day, more at first. Everyone learns differently. I know that as a former school teacher of many years. Some can read something and digest it immediately, even to the point of those with photographic memories. I'm the opposite. Memorize, memorize, digest, memorize. I aced the 8 tests in one day. Do whatever you have to to learn the stuff. And keep in mind that DM requires a huge knowledge base. I hope to finish up soon with the pool skills. I can't say from experience, but I'll bet that you'll use about 20% of what you learned in the course when actually DMing. It's a lot of knowledge explaining that there are reasons why one should take everything one learned in OW class seriously. And, this knowledge I'm sure allows one to answer "why" questions from students. I actually used maybe 20% of the knowledge I received in 6 years of college when I was out teaching Band for 20 years. But it was nice to have that large knowledge base. And like the DM stuff, much of that information was quite interesting as well.