I wonder how you went through the
OG. In terms of verbal, as I repeatedly preached, it is THE verbal bible. Take it seriously and I can guarantee you that if you do understand the concepts explained in it, you will do 80%+ in verbal in the test. Of course, certain verbal explanations will not be crystal clear but that is when gmatclub will come in handy. Just post your questions and others will gladly answer your queries. Just make sure that you also participate as it will ensure that you really understood the concepts: Once you can explain something in your own words, you are bound to have mastered the given concept. For RC, I would suggest you to read the sticky "very scared of RC" in the "GMAT" forum.
In terms of Quants, there is definitely much room for improvement. Luckily, quant is much easier to improve, for the average test taker, than verbal is. I would perhaps not suggest you to do all of the PS in the
OG. Maybe do the last 150 PS questions. DS, do the last 150 also although the last 60 may be overly difficult. Each time, try to understand the concepts being taught. You may be able to solve a problem but did you solve it in the most effecient manner? Maybe not. Remember that next to all Quant problems are solvable within 2 minutes.
PR gave you the basics in terms of quant. You now need to build on that basic. The next step up would be for you to purchase Kaplan800 as it really has good verbal and quant questions with clear explanations. Trust me, it is worth the investment. One thing you may want to look at is probability/combination rules. I know that in any of the book I studied, it was a neglected topic. Go through these forums work out those questions. Go through the probability guide provided free of charge in the forum. I knew nothing about probability/combination before joining this forum and I can do most of those problems here within the 2 minutes time frame. I even find those problems easier than many other question types(ie number properties). Remember, do not leave anything untouched. If you are weak at something or do not understand certain fundamentals, work on it, make sure you know how to
solve the same concept under different settings. The GMAT fundamentals being tested is very narrow but the creative ways in which the questions are asked makes it that it is very broad. You must have known that by now
After all this, make sure that you manage your stress level. No matter how good you are at during practice, you HAVE to keep your composure during the exam. This is another aspect of the test that will affect about 25% of your GMAT score if not more. I would suggest you to read the invaluable advice given by crackgmat750 as he gave phenomenal insights into the exam. Here is the link:
http://www.gmatclub.com/phpbb/viewtopic.php?t=10440
Feel free to ask if you have any other question.