Don't represent yourself even if you're going to plead guilty. The people in the court system are experts in their field and you'll have no chance regardless of how smart you think you are.
Think about it this way, you are master painter and some DA that has never done any real labor in his life thinks he can paint the same sized room as you with the same craftsmanship and efficiency.
Or someone thinks they are tough guy because they did 10 years in the pen, their entire body is tatted up and bulging with muscle from a decade of lifting, is he going to be able to hang in the ring with a pro boxer? Nope, boxing is not the ex-cons craft.
If you are not a legal professional, you're gonna get the worst of things trying to go head to head with someone that is.