Arslan,
Studying for the PMP Exam is a very personal matter. Everybody learns differently and everybody has different points of weakness. Therefore I can only give you general ideas and you yourself must know if these work for you or not.
First of all I think that you are using too many different books and sources. You are using The PMBOK, The PM PrepCast and the books from Rita, Heldman and a third book to study. That is too much. Generally speaking you should use a maximum of 2-3 sources. You are using 4-5. The problem here is that you may confuse yourself. I believe that the PMBOK, PrepCast and the books from Rita/Heldman more than are sufficient.
There is no "best way" to study the PrepCast & PMBOK. But what many students have told me is that they first listen to the PrepCast and then read the chapter in the PMBOK.
You say that you are spending 3-4 hours of study. Is that per day? That is definitely sufficient.
I think that you did a good thing to have a vision & mission for your PMP exam. That is a very good approach. Not many people do that.
Lastly let me ask you this: Are you taking any sample tests? Remember that you will have to answer 200 questions in 4 hours. That is what you have to practice, practice, practice. So I recommend that you listen to the PrepCast, read the PMBOK study books but most importantly that you take sample exams.
There are hundreds of free questions available on the internet (some good, some bad, some extremely bad). Answer as many as you can of these. But I also recommend that you sign up for an online Exam Simulator so that you can take "real" sample tests. I always recommend
www.pmprepcast.com/readysetpass.html
Until Next Time,
Cornelius Fichtner, PMP, CSM
President, OSP International LLC