I slouch, but that's okay, since slouching is cool.
You don't ever see cool people sitting up straight, do you?
If you're cool, you're a rogue, and your style shows it.
And glasses... glasses are cool, too, if they're not too big (Small, oval glasses are more attractive than big square glasses- you must avoid big, square, glasses at all costs) and if they're well-taken care of. Smeary glasses, or glasses with messed-up rims, show the world what a disgusting little slob you are.