Keep an eye on the clock so you don't spend too long on one question. You can always leave it and come back to it later. Read the question carefully. If you don't understand the question, read it again until you understand exactly what it is asking you. After reading the question, try to answer it BEFORE reading the answers. By thinking of the answer first, you are less likely to be fooled by a wrong answer. As you read through the possible responses, mark off the ones you know are wrong. This will save time if you have to come back to the question later. But read all 4 answer options before picking one. It is important to read all the answers, and not just take the first correct answer you see. Don't select a response just because you remember learning the information during your studies; it may be a "true" statement in its own right, but not the correct answer to the question.
If you do not know the correct answer, try to see which answer options are definitely wrong. If you have to guess, make sure you first try to eliminate as many wrong answers as possible first. Try to leave enough time to check over your answers at the end. It is important not to waste too much time trying to answer any one question. Choose an answer at random, but circle the question number so you can come back to it later if you have extra time after you have completed all the questions you do know. Go on to the next question. Use whatever time is left over at the end of the test to tackle those very difficult questions.
After you have finished the test, go back to those questions you circled as being too hard or as having no right answer. See if you can answer them now. Take as much time as you have. Never leave a test early, unless you are sure you have answered every question correctly. If you still cannot answer the question, then guess. You have a 25% chance of getting it right anyway; more if you can eliminate one or more of the wrong answers. Never leave a blank on a multiple-choice test.
If you are giving essay-style answers, spend the first 5-10 minutes of your available time noting down the ideas you wish to include. Put them in a logical order and write your answer. It is a good idea to practise writing this kind of timed answer as part of your revision routine for English and Insha.
Don't expect to know everything It is highly unlikely that any student will answer all questions correctly. So, don't panic if you see a question you did not anticipate or prepare for. Use everything you know about the content of the course and your own reasoning ability to analyse the question and identify a logical answer.
Before beginning your exam, make sure you are calm, relaxed and confident. You have worked hard, and there's no use in being nervous now. The more calm you are, the better you will perform.