I passed my exam today and it was quite a ride.  I had to squeeze in my preparation time between a full time job and my family (who was very supportive, otherwise it had not worked).  Here is how I prepared myself:

Application to take the exam

I filled in the form in August having the plan to take the test late fall.  I knew I could easily fulfil the requirements but I wanted to make sure everything is approved and cleared (in case of an audit it would have taken me a few weeks to bring the evidence as I moved to the U.S. recently and the contacts I provided are all except one in Europe) before focusing on learning.  Not surprisingly the application was approved a few days later.  I scheduled the exam shortly after receiving the approval to set a deadline and have a date to work with.

First start

I completely underestimated the effort!  I did not really inform myself properly what is required for the PMP exam and had the expectation that with my experience and the classes I had already taken on project management during my professional life should be fair enough.  I signed up for a PMP prep class at NYU in NYC for four days over the course of four weeks (September/October) and started researching what is required to pass the exam.  Doing the research on the Internet I got a little scared--I immediately purchased the PMBOK and started reading it.  It didn't take long that I figured out that this book may be great as a reference but one of the worst books to learn from (and remember the details).  However, I had 'read' the book once before the class started late September.

Structured approach

The preparation class at NYU was a complete waste of money and time!  Not recommended at all.  I wish I had rather used that time to prepare for myself.  I got basically two core pieces of information out of the class: 1) Structure your preparation time by reading one chapter in the PMBOK per day, then take tests on this chapter.  Questions on a 'per chapter basis' are for example provided in PMP Exam Success Series: Exam Simulation Booklet, the one our instructor recommended.  I bought that book but decided to also use the PMP Exam Success Series: Bootcamp Manual (with Exam Simulation Download) and ordered that book as well.  No Rita, I did not buy nor use her book. 2) What you read in the PMBOK is not enough.  There are things asked that are not in the book, such as code of conduct, all these motivation theories in detail (Maszlow, Herzberg...), Theory X, Y and Z, just to name a few areas.  For this information I paid $800 to NYU.  All the additional details we were given in class were way too high level to be sufficient for the exam.

Learning phase

I started intensely in the last week of September following the suggested approach, slightly modified: I started off with taking the tests (30 questions) for the chapter I was planning to read that night in the PMP Exam Success Series: Exam Simulation Booklet, then continued with reading the chapter in the PMBOK, and afterwards reading the same chapter in PMP Exam Success Series: Bootcamp Manual and taking the test there again (30 questions per section plus detailed review of wrong answers).  The Bootcamp Manual provides tons of additional tests and ITTO questions, I skipped those because it took me too long.  I managed to do a chapter per day on most days, I had a delay of 4 or 5 days for the entire PMBOK.  I hated the layout of the Bootcamp Manual, it was horrible and also not structured in a way you could easily remember things.  But it filled the gaps the PMBOK did not cover very well.  After I was done, I took the Oliver Lehmann 175 free questions and made horrible 56% there.  So I went into the PMBOK again and started reading, not front to back but all chapters in an order I decided.  Roughly again one chapter a day.  The last week before the exam I signed up with PMStudy.com and purchased the 4 sets of 200 questions for $60.  I did one of them every night (percentages: 1st set of 200 questions: 65.71%, 2nd set: 70.29%, 3rd set: 73.14%, 4th set: 70.86%) plus detailed review of wrong answers.  I took the downloadable test of the Bootcamp Manual, the rate was also somewhere at 75%.  I used Rajesh Nair's notes to repeat the material in a compressed way, they are GREAT once you get familiar with the layout.  I used the formulas here from pmzilla and read them many times over.  I took a couple of other free online tests, most of them were rather easy and I scored arund 80%.  I did not in particular try to memorize all the ITTOs as it was pretty clear to me that there are simply too many to remember them all, I also never took a test focusing on ITTOs only.

Exam

So I had a prep time of approx. 7 weeks with at least 7 days where I did not open any book or do any quizzes as I had other activities (work/family).  I had spend about 5 hours every night learning on the other days.  I went to the exam with a strong feeling that I am not at all ideally prepared.  The exam itself was very hard in my opinion.  Sure, there were very simple questions (maybe 30).  There were another 40 questions that were very similar to questions I had taken in the PMP Exam Success Series books mentioned above and at PMStudy.com (including all the calculation questions; those were very simple, too).  The ITTO questions were much easier than in the tests I had taken before (maybe another 10 questions).  The rest was hard.  I had to 'translate' them into something I thought the question might refer to and then eliminate the answers that are obviously wrong, usually those were two of the anwers.  This left me many times with 50/50 chances where I finally just chose one answer by gut feeling and others by 'that sounds right'.  So of all sample questions I saw before, many are getting close but none of them are really covering a major part of the exam.  The difficulty level is comparable to PMStudy.com.  However, many of the sample tests are confusing just by the way they are asking the question with all these "best", "not", "except" questions and then sometimes another negation in the answers to make things even more complicated.  I did not have one of them.  All process related questions were "what is the PM doing first?" or "what is the PM doing next?".  You better have a great understanding of the process sequences.

I was hitting the famous wall right in the beginning, I had problems writing down the formulas for SPI and CPI correctly!  Unbelievable, I knew them too well.  Luckily I marked about 10 questions in the first 30 minutes for review.  After these 30 minutes, I was in 'testing mode' and at the end I made a correction on almost every question I had marked at the beginning.

Lesson Learnt

There is no other way, you have to perfectly understand the logic and the structure of the PMBOK, you have to be able to memorize p. 43 in your sleep.  Do many, many tests but make sure to not only read through the answers and move on but understand the background by looking up every wrong answer you made, understand the logic, read the context of the surrounding area when correcting your test results.  I did 7 or 8 full 200 question tests.  Just correcting the results of each test took me many hours, often more then the test itself.  Everybody says you should receive an average of 85% on your mock tests before taking the exam.  I never reached that, but after having done the sample tests and thoroughly revising my mistakes, I think it didn't make sense to take the same test again but rather move on to save time.  And in the end, remember, passed is passed and you definitely are allowed to answer a lot of questions incorrectly and may still pass.  When preparing, make sure to understand the math and the critical path with schedule compression and you might already have gotten 10-15 questions right without a lot of effort.

Hope this helps anyone and good luck!!!