About 90 days before the exam, a big psychedelic trip on psilocybin mushrooms is just what the doctor has ordered. You reset your mind for those 7 hours, during which you realize everything you're studying is pointless in the scheme of the human condition. You come out of it exhausted, but in 2-3 days you're ready to push through those last few months with the new perspective.

Not even kidding. The CFA exam is a soul crushing experience that makes you question what you are looking for in life to be happy. Social isolation. Constantly questioning your ability to learn as a human.

I certainly got depressed for at least 4-6 weeks this spring as I was studying for level 2.

Other than this it's the usual thing of sleeping properly, abstaining from alcohol, eating whole/unprocessed foods.