Here's my study plan. Using a similar set of books (
MGMAT set, OG12, Quant/Verbal Review) for my May 17th test:
1.) Take diagnostic test to see where you are at. Mine was GMAT Prep 1. You may want to skip this step since you've already taken the real thing.
2.) Start working through
MGMAT Guides. I did all the problems at the end of the chapters, but skip the
OG Sets for now to save time.
3.) One you have gone through all the guides, take another diagnostic test to see where you are now at. Hopefully there is improvement from initial diagnostic test. I haven't reached this step yet, but will take either an
MGMAT Test or GMAT Prep 2.
4.) At this point, start working through the
OG sets listed in the
MGMAT Guides. If you go through all the problems listed in the guides, I believe you will have done
all of the
OG problems. Make sure to keep an
error log to help see where your weak spots are.
5.) Work on brushing up weak spots. At the same time, start doing the
MGMAT CATs that come with the purchase of the guides. This will help you get your timing down for test day.
6.) Look for other resources online, either free or paid. There are plenty of sites that offer free CATs, so these could supplement your studying. Also, there are some great resources listed on the forums here, such as the 700-800 level math problems created by Bunuel. If you're gunning for 750+, you will need to be getting problems like these right on your exam.
Best of luck in your studies. I have one more month to you to fit all of this in (with my May test date), so you might not be able to do all of this. If not, take what you like, and go with that.