Hi avinash2287,
There are a variety of Tactics (both mental and physical) that you can use to improve your performance during the GMAT - unfortunately, 'highlighting' text is NOT one of them. From what you describe, it's not clear how long you've been studying, so before I can offer you any additional advice going forward, 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? How many hours do you typically study each week?
2) What study materials have you used so far?
3) On what dates did you take EACH of your CATs/mocks and how did you score on EACH (including the Quant and Verbal Scaled Scores for EACH)?
Goals:
4) What is your overall goal score?
5) When are you planning to take the GMAT?
6) When are you planning to apply to Business School and what Schools are you planning to apply to?
GMAT assassins aren't born, they're made,
Rich