Surprised nobody here has mentioned sense-immersive studying. I've found immense success with it, and I've saved more than a few people's asses with it.
What you need for each subject:
1 bottle of knockoff cologne/perfume
1 package of sugarfree gum
1 phone w/usb cable
1 Set of notes
Pick a scent + taste combination for each test. Each session ideally takes one day. If you're panicking right now, simply do Round I for each one, eating a snack and washing up a bit in between, you can probably fit 3 of them in in an 8 hour period.
1) Spray the cologne on, and start eating a candy.
2) Record yourself reading your notes.
3) Take a break.
1) Add a spritz of cologne and get another candy.
2) Listen to your notes and take notes on them by hand.
3) Take a break.
1) Spritz + candy.
2) Listen to your notes and read along.
At this point, you're finished with the hard part. Copy the recording of your notes to your phone, set your alarm, put the cologne and candy in your bag, and go to bed.
When you walk into the class, spritz yourself on the wrist with a bit of cologne, rub your wrists together, and then rub them behind your ears. When you get your test, put a hard candy in your mouth, and take the test.
YMMV, but the general "feeling" you get is that you're remembering a lot more than usual, and the answers just kind of flow, rather than you having to go look them up.
Fie- voodoo, y duz et work m95?
The senses are intimately engaged in the human memory process, which is a reason why immersion is so effective in learning a language. We all have experienced brief flashbacks triggered by sights, sounds, and other sensations. By selectively immersing yourself in a given topic, you embed sensory links to the pathways involved in studying. The kicker is that because you are controlling the input to the taste and scent subsystems (which are the most powerful), you've basically got a direct pointer to the associated sense memory that you can invoke on demand by simply spraying on some cologne and eating some candy.
Bonus: Cyberzen Mode
Again, YMMV, but this seems to be extremely effective, especially when you're studying for multiple subjects and only have time to do 1 or 2 rounds with them.
Instead of going straight to bed when you're finished, copy your recording of yourself to your phone, pop your headphones in, and start listening to the recording. Set things up so that your laptop is playing relaxing music (80s-90s new-age is great, like Enya, Davol, Yanni, etc.) loud enough that you can barely hear it over the sound of your own voice coming over the headphones.
At this point, feel free to create some further ambiance (incense, candles, scented oils, fireplace, etc.). The key is that you want to be /comfy/. Once you've brushed your teeth and all that, and you're ready for bed:
1) Get into a comfortable sitting position.
2) Pay attention to your breathing/the sounds around you/your own voice/etc. Let your mind wander. If you itch or whatever, just scratch- be comfy.
3) When you feel like it lay down in the position of pic related.
4) Take 3 deep breaths.
5) On the 3rd breath, breathe out very very hard.
6) Sink into the bed- don't worry about falling asleep, just be.
7) Get up, feel refreshed and a little weird, go to the test.
8) Spritz + candy, take test.