width=280Giselle Weybrecht, London Busines School graduate, and author of The Sustainable MBA shares her GMAT tips for the world's most influential business school admissions test.

After hours of research, attending fairs like the QS World MBA Tour and speaking to students, I made the decision to study for an MBA. Little did I realize at the time that, out of the many application requirements, the GMAT would prove the hardest.

The GMAT is unlike other tests that students take in school. You cannot stay up all night studying and achieve a top score of 800. The test isn't easy, but the good news is that if you are disciplined and prepared you can get the score that you want.

Here are ten tips to help you prepare as much as you can for the GMAT:

-   Give yourself time. Don't book your test at the last minute, and don't leave the studying until the last minute either. Give yourself as much time as you can.  I knew that the GMAT was going to be a challenge, so I began my preparation early and put aside a lot of time to study (and to retake the test if I needed to).

-   Pick up the materials. There are a wide range of GMAT study books. Some of the best books are the official ones, with retired test questions. You can either buy these new, from current students or at used bookstores. You can also find free practice tests on the GMAC website.

-   Familiarize yourself with the format. The GMAT is a timed test in three main parts. The analytical writing assessment (one hour), the quantitative section and the verbal section (both 75 minutes). GMAC provides a list of possible questions for the analytical writing assessment so there is no excuse for not being prepared.

-   Find your weaknesses. Many GMAT books will have a sample test you can take to get you started. Take this exercise seriously. This will give you a taste of what to expect and help you to determine what you need to work on further.

-   Find out what score you need. Different schools announce what GMAT scores they are looking for. It is important to know this before you get started.

-   Make a study plan and stick with it. Put together a study plan that works well for you. Determine what you need to work on and consider studying different parts of the test on different days. I picked up every GMAT practice book I could find and systematically studied the questions until I understood how to answer them.

-   Learn the tricks. The GMAT test is made up of a series of questions of different types. Obviously each question differs, but the methods used to answer them generally stay the same. Familiarize yourself with each type of question, and develop a process for answering each one.

-   Don't forget the timing. It isn't enough just to be able to answer the questions correctly; you need to be able to answer them quickly and under the pressure of time. Try setting yourself time limits during practice tests. Don't forget, you have to answer all questions or it will count strongly against you.

-   Connect with others. If you feel you need some additional help, look at the wide range of groups or one-on-one courses that exist. These can get expensive but for some people this can be the way to go.

-   Enjoy it. Studying for a test is never fun, but many people turn it into a challenge, even a game. I charted my progress and rewarded myself for staying on track. In the end the hard work paid off and I achieved the score I needed.

My biggest piece of advice is not to stress. First of all a perfect GMAT score is not necessarily going to get you into a business school. If the rest of your application is weak, you'll have problems getting into most schools.

On the other hand, if your application is a little weak, a high GMAT score can help. You can retake the GMAT - I took it twice. The first time I achieved near perfect scores on the verbal and essay sections, but scored terribly on the quantitative section. I knew how to answer the questions, but I hadn't spent enough time practicing answering them under time pressure. I took the GMAT again to bring up my score, and fortunately the second time around I managed to achieve what I needed.