Hi Varun,
It sounds like you're just starting out. Is that true? Have you done any studying so far?
If you're just beginning, then it would be a good idea to take a FULL-LENGTH practice CAT Test; you can download 2 for free from
www.mba.com (and they come with some additional practice materials). Before taking your first FULL CAT, you might want to spend a few days familiarizing yourself with the question types and general content/format, but you shouldn't wait too long to establish your 'baseline' score. A FULL CAT takes about 4 hours to complete, so make sure that you've set aside enough time to take it in one sitting. Once you have those scores, you should report back here and we can come up with a study plan.
I'd like to know a bit more about your timeline and goals:
1) What is your goal score?
2) When are you planning to take the GMAT?
3) When are you planning to apply to Business School?
GMAT assassins aren't born, they're made,
Rich