Like others have said - read the books. You won't need to memorize stuff in tables, but you will need a feel for the numbers ("at what distance is a 22lr considered lethal?" with multiple choice answers...) Listen during class. That did it for all the people in my courses, and some of them weren't what anyone would consider the brightest bulbs in the pack (and many had absolutely zero firearms exposure). Some of them didn't even read the book. The test is multiple choice and True/False. Everyone passed.
If you are concerned, google for PAL and RPAL summaries, notes, instructor's notes etc. I found several online that were 10-15 pages long and covered all the key points. I read those through a few times the night before the test. Was overkill, but made me feel better.
For the practical -
1. take your time during the test. Don't rush anything. That is how lots of folks made mistakes. Be methodical.
2. focus on muzzle control. This is especially tricky with RPAL (it is easy to point in the wrong direction with a pistol).
3. take every opportunity to practice ACTS/PROVES with the firearms they provide, so you are familiar and have physical practice.
4. Speak to the examiner. You can say "now I am doing this." If you accidentally forget a step (by rushing, for example) you can say "oh I wanted to do X but I didn't, can I start again?" - they will usually let you start over.
5. Review the rules for a fence crossing - every time you put the gun down, you have to ACTS and PROVES when you pick it up again. This got lots of people in my PAL group. Basically, EVERY TIME YOU PICK UP A FIREARM, ACTS/PROVES. Doesn't matter if you "kept it in sight" or you "know it is unloaded."
I was a little stressed beforehand, but afterward realized there was absolutely no need to be. Enjoy the course! And yes, take BOTH PAL/RPAL. More RPALs are good for all of us oppressed gun owners.