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Never stay up all night studying. If you've left enough time and started studying early enough before the test, this last-minute cramming session should be unnecessary anyway. It will only result in an improper understanding of the material and a lack of focus during the test. The best way to make sure you do well is to be well-rested for the exam. Your brain actually transfers information into long-term memory while you sleep. Getting enough sleep will help your brain store all that stuff you're studying so you can recall it later. Just like with studying, you should make sure you're well-fed for the test itself. Have a bigger breakfast than usual the morning of a test to keep your brain nourished and focused. If you have the test later in the day, pack a small snack like a granola bar to keep in your bag. Eat it quickly before the test to keep your brain going. Eat complex carbohydrates, such as whole-grain toast or oatmeal. These digest slowly so you won't experience a crash during the middle of your test. Eggs are a good choice. They contain protein and choline, a substance that may boost your memory. Have a little lox on a whole-grain bagel. Studies suggest that eating fish rich in omega-3 fatty acids, such as salmon, can help improve your brain functioning. Have a cup of coffee or tea if you'd like. Caffeine may benefit your memory, according to some studies. Looking over your notes a few more times can be beneficial. You might catch something you missed before and end up getting an answer right on the test because of it. Do not, however, spend the entire day cramming. If you've studied effectively, this is unnecessary. You'll end up stressing yourself out and by the time you take the test, your brain will be too tired to concentrate. Instead, just look over your notes over breakfast, and maybe once more the period before the test. Any more risks wearing out your brain before you even take the test. While it sounds silly, this can be a huge distraction during a test. Your brain will have a tougher time focusing on the test if it is distracted with this. Also, you may not be allowed to go to the bathroom during the test for fear of cheating. Eliminate this worry by visiting the bathroom before the test period.
Get a good night's sleep. Eat a good breakfast the morning of the test. Study only a little the day of the test. Go to the bathroom before the test.