There are many, many ways to drive yourself clinically insane. One way is to infect yourself with Treponema pallidum, the causative agent for Syphilis. Another way is to take mind-altering drugs over a long period of time, such as psilocybin, Baeocystin, lysergic acid diethylamide, or even methamphetamines. Yet another way is to intentionally be exposed to a known vector of rabies. Try going to a park and looking for animals that display odd behavior- that fox that's trying to do back flips off a bench could be a worthy candidate. Once infected, the rabies virus will make its way to your brain stem, and in a matter of weeks, you, TOO can be mentally insane! A final way is to dive for gold deep in the Amazon rain forest. One, you'll go insane because there isn't much there, and 2.), you'll go insane because of the high Mercury levels in the water from the mercury used to separate silt from gold.
BUT WAIT!! Is there a way that I can force myself over the edge without injuring myself with external means?
YES! You Too can become insane in three easy steps!
1.) Study astrophysics, strange particle physics or the most dangerous, the math of infinity.
2.) Try to explain the workings of the universe or the levels of infinity by yourself.
3.) Sit back and (relax?) while your brain convinces itself that it is correct when it actually isn't.
This easy Three Step Process can take a while to complete, as your brain needs time to ferment and fester on certain discreet ideas or theorems.
BUT IT WORKS! Just read the following.
Georg Cantor, notable German mathematician, attempted to discover an infinite set theory or something of the sort. He proved himself correct, then incorrect usually on a monthly basis. His certainty of his calculations then his inevitable proof of the opposite gradually led himself to insanity.
Ludwig Boltzmann, Austrian physicist and mathematician, was driven insane by the following: S=K.log W. Yes, one of the greatest minds history succumbed to utter madness by an equation to determine amount of entropy in S.
As a conclusion, the best way to drive oneself insane is to infect oneself with a mind-altering pathogen (Rabies, Syphilis, Prion etc.), take psychotoxic chemicals repeatedly (try to get some tainted with foreign chemicals- they might make you rip your face off because it feels to darn big), or try to explain the universe in a simple, yet elegant equation. I most definitely recommend the latter, seeing as the previous options will leave you depraved, quite silly, and ultimately dead and gone. And who knows? Maybe in the process of trying to go insane, you'll explain the universe.
It's definitely worth a shot.