In order to prepare for an important  test you will need to get at nine to eleven hours of sleep This will allow your brain to be more active during school hours. You can also eat a nutritious breakfast because it is important that you get the day started on a good note. This will make sure that you have no distractions during the test and your brain will be focused on the test and not your belly.  During your test you will want to take as much time as possible and if you dont know a question make an educated guess.