Hi sashankvissa,
Since it's been about 2 years (or so) since you took the GMAT - and it's unclear whether you've done any consistent studying for the Test since then - you're essentially starting 'from scratch.' As such, it would be a good idea to take a FULL-LENGTH practice CAT Test; you can download 2 for free from
www.mba.com. That score will give us a good sense of your current strengths and weaknesses and will help provide a basis for comparison as you continue to study. 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) Do you have a Test Date scheduled in September yet (and if so, then what is it?)?
3) When are you planning to apply to Business School?
GMAT assassins aren't born, they're made,
Rich