Don’t drink alcohol, don’t smoke, don’t do drugs, get to bed at a reasonable time, exercise, and eat a well balanced diet. Also, wash your damn hands. None of the vitamins will matter if you’re staying up late, eating poorly and practicing bad hygiene.
Agree with all of this, but definitely out of all these things, do NOT smoke weed. It WILL kill your memory. A beer here and there (no more than two of low ABV under 5 percent) would be ok after a stressful mock.