First I would say that you are just not stupid enough, but with a little practice you can.probably fake that. Watch Forrest Gump a number of times. When you can make him look lime genius, you are probably ready.
Next. Lie about everything. It doesn't matter how small or trivial the question, lie. If ask, lie about the lie.
Third, remember that you are the smartest man in the world, and women don't count. They are just sex objects, and only if they have big tits.
Finally, if you feel that you don't want to answer, just attack the questioner.