I recently scored 740 on the GMAT test. I was quite surprised to score over 700 considering I had only spent 3 weeks on prep.

A lot of people asked me whether I did anything special to get such a good score. Rather than keep repeating myself, I thought I'd create an online reference so others can benefit from it.

The GMAT is divided into two sections: Math and Verbal. Since it's rather difficult to improve your English in a few weeks, I spent 90% of my time working on the Math section. By spending 4-5 hours a day for 3 weeks on math problems, anyone can improve their math skills dramatically.

Its possible to boost your verbal score too, through the same amount of effort, but it's a lot more difficult since it is inherently a lot more boring. Instead I suggest improving your spoken English(if it's not very good) by watching a lot of movies and reading a lot of English books. Obviously this is not something you can accomplish in 3 weeks so I suggest you start out several months before you plan to take the test.

But if you're like 90% of the population, your math skills could definitely need some improvement. The good news is that you actually can work on this in 3-4 weeks.

I strongly suggest you buy the Kaplan Premier book. It contains a CD that has actual computer based tests on it. These tests simulate a live environment and are timed. They also calculate your score for your. The questions are a lot tougher than the actual GMAT questions so don't be disheartened if you don't score very well on these tests. I didn't score more than 610 in any of the tests(I gave about 6) but my average score was only 560 on these prep tests.

I also solved the Kaplan 800 book which has a list of the most toughest questions and I strongly recommend solving that after you're done with the first book.

However, if you're a non-math person and are finding the math tough, particularly the probably and combination problems, I strongly recommend reading Innumeracy: Mathematical Illiteracy and Its Consequences. You should be able to get it at your library or buy it online for $5. It's an easy to read book that gets you thinking about using numbers in everyday life.

I had also given a practice test at a Kaplan center, but it was written and thats the same as the online computer-adaptive GMAT. I scored around 575 on that test which really depressed me but I still didn't go for the Kaplan prep courses. If you can spare the $1500 for the course or think you need the motivation of a classroom setting, you should go for it. I personally don't think I could've done better with a course.

The one thing I strongly recommend is doing all the practice lessons and tests on the Kaplan CD. It will really help you devise a strategy for quickly solving the problems in time.

One of the things I realized was that I was rushing through questions in order to finish the test within time. This was causing me to make mistakes and lowering my score. In the exam, I took my time on the first several questions. In fact, for the first 2-3 questions, I spent nearly 3-4 minutes on each one. The GMAT adapts to your level of math and gets progressively more difficult. If you get the first several questions right, you have a very good chance of getting a high score.

Half way through the math section, the questions were so tough, I immediately knew I couldn't solve them. I skipped 2 such questions and thus made up for lost time without significantly impacting my score.

Here is a complete list of the best GMAT prep books I used. I strongly recommend you use these books.

Even if you're not planning on going to Harvard or Wharton, you might think you can get by with a 550 score. However, one thing you might not be aware of is that with a 700+ score, even if you go to a 3rd tier college, you stand an excellent chance of
1. getting your application fee waived
2. getting a full-ride (a full-ride isn't a free car, it's a scholarship that pays all your fees!).

So don't slack off on your preparation just because you want to go to a 3rd tier college.

UPDATE: I got into UCSD & USC with tuition waivers and UCLA (all in the 3rd round, which is typically the toughest)