Preparing for tests might appear difficult especially if you have too little time, you'd have to make the most of that time and focus on passing the test itself.
• Know what to expect-the nature & type of the test.
• Learn how to pace yourself. Allocate adequate time for each question and do not spend too much time on difficult questions. Answer the easy ones first and then return to the difficult ones.
• Keep track of time during the test. Do not let time run out on you!
• Learn when and how to guess. Eliminate wrong choices before finally picking a guess.• Check your answer sheet regularly to be sure you are not writing the right answer on the wrong place.
However, you should generally try to read widely to improve your reasoning and vocabulary.