These hints are about taking exams, not preparing for exams as that is another matter. 

Every student can benefit by knowing basic steps needed to take exams at the university level. Practicing these steps can help you make better grades.  

 1.  Assume a confident attitude:  Confidence is derived through preparation.  An exam is a tool to measure how much you have learned, nothing more and nothing less. Your success will depend as much on your “attitude” about the test as on the specific “methodology” you used to prepare for the exam.  A calm and self-assured demeanor will allow you to reach the highest score your level of preparation will allow.  As you enter the classroom, being anxious about what you don’t know, how much you studied, or whether you studied for the right thing is no longer of immediate concern.  That stage is past, now is the time to perform with what you know.

2.  Remain calm, relieve stress:  try to remain calm before and during an exam.  Take a 20-30 minute break before the exam to clear your mind.  If you keep looking at your notes you are not allowing your brain the opportunity to process and organize information.  If necessary, practice some calming techniques known to relieve stress (deep breaths, a brief walk, closed eyes, thoughts about something soothing, etc.).  You will do better if your mind is at ease and you are not stressing.

3.  Familiarize yourself with the exam:  when you first receive the exam, scan it quickly.  This way you will know what sections are included and there will be no surprises.  Sometimes answers from one section and assist you in another section.  Carefully read any directions provided.

4.  Don’t rush during the exam.  Work at a steady pace, pre-plan how much time will be needed for each section, plus allowing some time for review of answers. Don’t turn in your exam early unless you are entirely comfortable with your effort.

5.  For multiple-choice exams:  Read the directions to check if you should mark only one answer.  Answer each question in your head before you look at the answers.  If one matches your answer, it is probably correct.  Mark questions you are unsure of and come back to them later.  Read all the answers before selecting one.  Sometimes two answers will be similar but only one will be correct. Cross out any answers you know are incorrect. Get rid of them right off the bat. That way, you've narrowed down your choices.

6.  Don't get bogged down with a question.  Mark it, and come back to it later. Working on other questions may spark your memory about the answer to a previous question.

7.  Don't leave any questions blank. Unless your teacher has told you it's better to leave them blank, you should always try to answer everything, even if it is a guess. You may get partial credit, or better yet, you may get it right!

8.  Check your answers: Always go back and check your answers. Always. It’s quite likely you'll find at least one answer you wrote down can't possibly be right, change it, and receive credit for what otherwise would have been a wrong answer. 

9.  Don't panic:   When others start turning in their exams before you’re finish, don’t feel a need to rush. Not everyone works at the same speed. Work at your own pace.

10.  Ask questions:  Don't hesitate to ask your teacher a question to clarify something during a test. If something is unclear, ask and get a clarification.

Based on http://www.valdosta.edu/~grissino/geol3710/howtotest.htm