Using Realistic Material

First Practice only with realistic material. I can t emphasize this enough. Use the Official Guide. Take the GMATPrep practice tests. If you need more, turn to my sets of practice problems. The average book you take off the shelf at Barnes and Noble just isn t good enough.
Next Practice perfectly. I ve written a longer article about how to do so. In short Do fewer problems, but master them all.
If that means doing some questions over and over again, that s great. You re not finished with a question until you know how to do it, are confident in your approach, and can complete it in the correct amount of time for that question type.