As far as study materials go, the MGMAT products are great for the self-learner. Nonetheless, you should be sure to supplement your prep with Official Guide material and the Official CAT tests as well.
Even then, simply going through thousands of questions doesn’t mean you will see a commensurate increase in score. Understanding the areas where you struggle and identifying any patterns to your mistakes is key. Put another way, when you miss a question, understand why you missed that question and makw sure not to fall for the same trap again. Of course, whenever there is a tough concept the forums should be to answer your question.
Finally, you will want to make sure that you are making steady progress. Make sure to take practice tests at least every ten days or so (MGMAT CATS as well as the Official CAT mentioned before). And remember that every error you make is an opportunity for improvement.
Good luck, and let me know if you have other questions.
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