I'm using the same study materials. Here is what I am in the process of doing:
1.) Take a GMATPrep Diagnostic Test on mba.com
2.) Go through the
MGMAT Guides 1-8. Do problem sets at the end of each chapter. You could do the OG Problems as you go; I have decided not to, however.
3.) Take another Test to see how you have progressed after getting through
MGMAT Guides.
4.) Start over with Guide 1, doing all OG Problems listed. Keep an
error log to track your strengths/weaknesses. By doing this, you can see which areas you need to put extra time in.
5.) Now, start taking more practice tests, preferably CATs. By this point, you should have a good base of knowledge, now it's just a matter of getting your timing down so you don't run out of time on the real test.
6.) Continue looking for resources on sites like GMAT Club to aid in your studies.
Hope it helps! Good luck!