This site claims the techniques described work. Suggestions include;
When you have a test in front of you, close your eyes and just blink them open for a millisecond while you stare at the center of the page. This burns the image of your test or list or chart or whatever you're looking at in your visual cortex. By keeping your eyes closed for a few more seconds, all your mental resources can stay focused on just that one image. Then you're subconscious takes over and begins to work out the answers while you move to blink the next page. This process was used to memorize faces in a room, documents, layouts of buildings, etc... Then, most of the details could later be extracted in deep hypnosis.Deep Breathing [to relax]
Take a thick black marker with you into a test. In a multi-choice test, black out the options that you know to be subterfuge. This gives your brain less load to consider and improves your chances if you are just going to guess.
Subliminal Learning for Vocabulary
Hunger makes you alert. It may have something to do with our primitive hunter gatherer amygdala oblongata. If you are hungry, you brain processes information and cognitive demands much faster and more accurately.
Pick the Lowest Hanging Fruit First