Being a smartass is a topsy-turvy kind of personality. People who claim the title actually work hard to be that way, and have a lack of confidence to attribute to their arrogance, an ironic turn that feeds into a cycle of joking about everything (and sometimes doing stupid things just to get attention).
Surprisingly, there are a few ways to be a smartass. Although successful ones often relish the thought, mild depression or even frustration often expands ones ability to make a smartassed remark. In this case, the ability will subside after a short amount of time, unless these feelings are chronic. In that case, it is essential that these people seek professional help before they extremely piss off everyone they know and love.
Another route to take on the road to being a smartass is sarcasm. A quick, witty, sarcastic remark can have grandeurous effects on the target a smartass is attempting to poke fun at, or in some cases humiliate. While many see sarcasm as essential to smartassism, the only crucial part to being a smartass is the fact that you think --know-- you are right. Arrogance gives the smartass the mental feeling of power over others, which propels their thought processes enough to find inherent flaws in the things they seek to pick at.
A smartass, to be truly successful and even liked in the eyes of his smartass peers, must hold humor in their arsenal in a much higher regard than pure malevolence. When a target of a smartass (smartassee) sees the weak attempt at humor, they will inevitably say the smartass is, "Trying to be funny." Thus, the smartass has failed and made a complete and utter ass out of his or her self.
It is entirely too difficult to go over the incredible scope of a smartass in words. It is, above all, a feeling: a feeling of wanting, of empowerment (when executed correctly), and, deep down, a feeling of love for being right all the time.
Oh yeah, and a distinct sense of total asshole.