Here`s a tip that worked for me. I would draw out each system on a piece of paper, sort of like a blue print. I continued to do this until I could draw each system completely, every check valve, everything. Just reading about it didn`t do it for me, I had to be able to visulize it all in my mind. Another clue..emergency proceedures...memory items...being able to spout them out while listening to a fire bell ringing is completely different than just saying them in a controlled atmosphere. Really, really get them down cold. Another thing...no one cares about how you did it before, or how the systems worked on your previous aircraft....Good luck to you.