Hi Sunill,
From a statistical standpoint, you might not have to do anything differently to pick up those extra 10 points. GMAC has openly stated that your Official Score on the GMAT is within +-30 points of actual ability, so if you're scoring a 590 right now, you could actually be scoring 620 (of course, you might actually only be scoring 560, so you can't afford to get complacent).
When trying to figure out the categories in which you can pick up missing points, start by reviewing your CATs and focusing on ANY question that you got wrong because of a silly/little mistake. If a question is "gettable", and you get it wrong for a silly reason, then that's your fault and it's something that you have to fix as soon as possible. At this level, I would bet that there are plenty of questions that you could have gotten correct but didn't. Focus on proper note-taking, doing work on the pad, etc. and you'd be amazed how quickly you can get back those lost points.
Are you taking your Official GMAT next week?
GMAT assassins aren't born, they're made,
Rich