I prepped about two months. I first bought Peterson's Ultimate GMAT toolkit: catchy title, horrid book. Thank goodness that I soon read various forums and bought some good books. The ones I used are:
Princeton Review
Kaplan
Manhattan GMAT guides (verbal)
OG11 (of course)
PR and Kaplan provided nice, concise summaries on verbal strategies.
Manhattan GMAT books had more depth, and their content is excellent. Another great part of these books is that they reference the
OG by question type. For example, in their section on parallel sentence structure, they pick out all the related questions in
OG. I highly recommend this set of books, and no, I do not tutor for them (yet).
I focused on verbal in my study sessions, and towards the end, after I had the timing down pretty well on the practice tests, I did only the verbal portions. I quit doing the AWA after the first practice test. Tailoring my studies to my strengths turned out to be a good move, and I recommend this for everyone (in other words, don't keep grinding on tons of questions after you know a concept very well). I was able to improve my verbal score from mid-30's to mid-40's over my study period.
I did practice questions during the week, and I did roughly 1 practice test per weekend. Here are my scores, roughly in order of time:
PR 710, Kaplan 640, Kaplan 630, PP 740, PR 740, GMAT Prep 750, GMAT Prep 770, PP 770, Real Test 770 (V 50, Q 45).
Note: PR test software is buggy. During one practice test session, I got a verbal RC that was completely garbled. It had many lines with only one word per line, and the line numbering was messed up. I decided to skip testing that day and watch football on TV instead.
Don't worry if you don't see a steady progression. I was just fortunate in that I steadily improved my time management and verbal skills, and I did not have any "off" days. In general, it is more important I think that you feel better and more confident about your answers over time, and that your scores show a general increase and not necessarily a strict (i.e., monotonic) increase.
Best of luck everyone.