When you are taking a competitive exam like CAT it is not important whether you know more than others, how you attempt the paper makes all the difference. In the limited time at your disposal, number of correct attempts has to be maximized, by attempting questions from your areas of strength. The only difference between a 99 percentile scorer and an average scorer is the correct choice of questions; the number of attempts doesn’t differ much.
There are many ways to effectively analyse the paper and that comes through practice. One of the ways is to take mocks. After having appeared for the mocks, take a moment and figure out how many of the questions were in your comfort zone and how many were not. If you cannot identify these questions from a particular topic, then that topic is a weakness for you and you need to fix that. Also, there will be some questions that will be extremely hard. Such types of questions are the speed breakers, which you should not attempt in the exam.
You need not attempt all the questions in the CAT exam. If you attempt a significant number of these difficult questions from a particular topic, then you will waste your precious time. Even attempting half of them with full accuracy will lead to a very good score and percentile. You should not miss the good shot questions, by good shot we mean the questions identified to be correct and could be attempted with high accuracy. As it is said, accuracy goes with right choice, if you select the right and do-able question, your accuracy will surely improve.
After every mock, also do a simple exercise to improve decision-making. Select at least three attempts from each section that you could have skipped, and replace these with three you could have attempted. In your first few mocks, you might even be able to select 5-6 questions in each section. The big gains in mocks come from improved decision-making and you have to take a conscious effort to improve this. If you can reach a point where you cannot find more than 1 question in each section that you had incorrectly chosen to attempt, you can count yourself ready for the D-Day.