Hi Rahul,
From your message, it's not clear whether you've done any prior study for the GMAT or you are just starting out. Many Test Takers spend 3 months (or more) of consistent study time before they hit their 'peak' scores, so if you're trying to 'rush' through your studies, then that might actually keep you from scoring at a high level.
As an aside, the 750+ score is approximately the 98th percentile - meaning that 98% of Test Takers never score that high (regardless of how long they study or the number of times that they take the GMAT). Thankfully, NO Business School requires a score that high - so it's important to realize that the score that you "want" and the score that you "need" to get into your first-choice School are probably not the same thing.
Before I can offer you the specific advice that you’re looking for, it would help if you could provide a bit more information on how you've been studying and your goals:
Studies:
1) How long have you studied?
2) What study materials have you used so far?
3) How have you scored on EACH of your CATs/mocks (including the Quant and Verbal Scaled Scores for EACH)?
Goals:
4) When are you planning to take the GMAT?
5) When are you planning to apply to Business School?
6) What Schools are you planning to apply to?
GMAT assassins aren't born, they're made,
Rich