Hello!
I recently sat for the exam and passed my CAP. I used the CAP Exam Study guide, while I can agree with others there were some minor errors in the book but IAAP did send revised pages, so overall the book was helpful. It has a lot of information! To be honest It was some what overwhelming for me to read it because I didn't like the way it flowed (In my opinion it was very choppy, it went from one right into the next).
So this is what I did, I rented from Amazon one of the books from the list (Procedures & Theory for Administrative Professionals 7th Edition Professionals total $23.00-they gave me about 4.5 months). Then I purchased the new study guide, so I actually read two full texts books. I like reading the book I rented from amazon since I liked the way it flowed a lot better, and it reminded me more of school, probably why it was my preference. After I was done reading that book I read the study guide, I found it much more helpful, as there were things in the first book that were in the study guide so it was a recap to me.
I study for weeks reading and making notes, and answering practice questions. Oh by the way the study book has practice questions at the end of each domain, that was really nice!
So yes that is what I did my notes were a great summary because I knew that in a few weeks I might forget so I was able to go back and read what I had learned weeks ago.
I hope this was helpful, let me know if there is anything you need me to clarify, or need help with.
I also have a document with "flashcards" you would just need to print them double sized and then cut them out. Warning there are a lot.

But I hole punched them and then placed them into a ring holder, and reviewed some of those as well.