I passed my exam above target this morning after a couple of months revising on and off. My suggestions for those who are preparing to take the exam is as follows
Prepare well - I actually don't think it matters much which book you use to revise. The key is for one to familiarise oneself with the processes described in the PMBOK using any tools available, be it flashcards, books, apps etc. I think the Vargas video is probably one of those useful tools that anyone considering taking the CAPM should watch at least once, it really allows you to see the link between the processes which is exactly what the examination assesses. I also did the Prepcast quizzes and I have to say that they are tough, so do not worry much if you fail them. The main thing is to go through all the questions afterwards - the ones you got right and wrong and use the opportunity to improve your understanding.
My exam tips are as follows -
Read the questions very well and if you do not understand it look at the multiple choice answers for potential clues to what the question is about
Be switched on but not put off by how differently the same question can be posed, for example don't expect the questions in the exam to be posed in exactly the same way as the Prepcast quizzes even though they are potentially similar
Learn the art of 'logical elimination'. This is where the Prepcast quizzes helped, it allowed me to master how to eliminate at least two incorrect answers from the options for questions that I was not sure about. Once you have you options narrowed down to two, then read the question again and see if there is a clue in there that points you to the right answer. You will need to be able to do this in the exam.
Lastly, study every aspect of Communication, Tailoring, Agile and the ITTOs. For the ITTOs I found that I was able to answer most of them without knowing everything by heart, what I did was look very carefully at the options given every time, and based on my knowledge of the processes eliminated the options that did not make sense either because there was a tool and technique given as an input, or because there was an input into a process that logically could not have been created yet because it was too early/late in the process. For example outputs from the Cost Management KA such as Cost Baseline will not logically be an input into Schedule Management KA because you do the Scheduling first.
Good luck!