I have a few for you:
- Be careful to answer the question asked. All too often GMAT test-takers unnecessarily miss questions even though they did basically all the work needed for answering a question but then failed to answer the question asked.
- In Verbal, read every answer choice from beginning to end. Often Verbal answer choices are half right, and half wrong, or the part of a choice that makes the choice correct comes at the end. So, you may be able to get a few more points on the Verbal section just by reading every answer choice in its entirety rather than deciding that a choice is incorrect or correct before you read the whole thing.
- Just a few patterns may cause most of your errors. So, to reduce the number of errors you make, any time you miss a question, immediately seek to identify and address what caused you to miss it. By identifying and addressing just a handful of error-causing behavior patterns, you may reduce the number of careless errors you make to almost zero.
- When learning Quant, learn the logic that underlies the formulas, strategies, etc. for each topic. In other words, don't just learn how to answer the questions. Learn WHY those approaches work and make sure you understand the essential logic of a topic. By learning the logic of a topic, you'll remember the topic better and also become better able to apply the concepts in a variety of situations.
- Do most of your GMAT practice untimed. If you do most of your practice timed, you won't have time to learn. Practicing untimed gives you time to learn to go through the steps that efficiently get you to correct answers. Then, once you're getting questions correct untimed, you can work the time per question down until you're answering them at test pace.
- When practicing for the GMAT, be VERY reluctant to give up on a question and just look at an explanation. The GMAT is to a large extent a test of finding ways to answer questions, and you won't develop skill in finding paths to answers by just looking at explanations. Rather, in many cases, you're better off finding a way to answer a question before you look at an explanation. Even if your way isn't very elegant or efficient, the exercise of coming up with that way to answer the question will result in your developing skill in creating ways to answer questions. Then, after you come up with a way to answer a question, you can go look at an explanation to see how the question could be answered more efficiently.
- One of the best ways to practice for the GMAT is to shoot for streaks of correct answers. Even getting 80 percent of questions in a topic correct doesn't really mean that you have the topic down. In contrast, if you can get questions in a topic correct in a streak of 20 in a row, you can be pretty sure you've mastered the topic. For detail on how to use the streaks method to master the GMAT, see this post.
How to Ace the GMAT Using the Streaks Method