Hi VarunW,
Raising a 530 to a 720+ will take some serious work - and you'll have to make some significant improvements to how you handle BOTH the Quant and Verbal sections. Thankfully, you've given yourself LOTS of potential study time, which is good. By focusing on the GMAT now - so that you can 'lock in' a competitive score - you'll likely find it less stressful to work on your applications later on.
That all having been said, you can proceed in a couple of different ways. You would likely find it beneficial to invest in a GMAT Course of some type (either Guided Self-Study or instructor-led). If you wanted to focus on honing your 'math skills' before focusing on GMAT style questions, then you could also do that. For free math practice and help, I recommend that you set up an account at Khan Academy (
www.khanacademy.org). The site is completely free and makes the learning a bit more fun and 'game-like' (as opposed to the dry academic approach taken by most books). While the site is vast, you should limit your studies to basic Arithmetic, Algebra and Geometry. After spending a little time re-building those skills, you could focus on your GMAT studies. Of course, you might be able to develop your math skills while building your GMAT Quant skills - so you should consider both options.
Most GMAT Companies offer some type of free materials (practice problems, Trial Accounts, videos, etc.) that you can use to 'test out' a product before you buy it. We have a variety of those resources at our website (
www.empowergmat.com). I suggest that you take advantage of all of them then choose the one that best matches your personality, timeline and budget.
If you have any additional question, then just let me know.
GMAT assassins aren't born, they're made,
Rich