Then when you take the test, wear that perfume. It can help you remember what you study because you relate the scent to the information. Of course you have to use a scent that you wouldn't normally smell. I usually listen to Beethoven while I do mindless homework like math, French, or science assignments. It gets your brain pumping and flowing, and keeps you alert and awake.
More fresh air means more oxygen to the brain.
Trust me, this really helps with memorizing and studying for school. This always helps. The chemicals in some perfumes may affect your power to concentrate and remember information. Other students will want to share their notes because they can read yours. This process organizes the ideas in your mind as you are doing it.