Coming from a situtation where I don't do math problems everyday, I also need some serious brushup on my math skills. I have taken many math classes (up to calc 3), statistics, and others so I have done a lot of math but that ended a few years ago.
This may be overkill but I have about 3 to 4 solid months (been studying since beginning June) before I think about scheduling an exam date. I have been studying 2-4 hours a day, Monday through Friday and nothing on the weekends

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My order of execution is as follows:
1) Arco's GMAT Math Refresher
2) Princeton Cracking the GMAT
3) Kaplan Premier 2009
4) Kaplan Math review
5) Manhattan guides (I have all of them)
6) OG 11
7) OG Quant
8) OG Verbal
9) sc/rc/cr 1000 (as needed)
10) last but not least are the gmat challenges on here.
The reason why I mention this is because I feel that once I do a ton of problems, I can approach new ones with better experience and therefore have a better methodology going through them.
I feel the best way to improve, according to many of the posts I've read, is to completely know the basics inside out, and then from there, do as many problems it takes so that when you come across a problem that you originally had difficulty with, the solution would be much easier to derive...
I'm taking the cat's (kaplan, gmatprep) towards the end of my prep - not sure when. I am lucky enough to have this summer off from school so I can focus exclusively on work and this exam....
fwiw,
- tsd