You don't have to go in a suit or your cocktail outfit mind you! LOL Just don't dress like a slob or wear flip flops or anything remotely undressing. Call me old fashion but nothing urks me more than dressing as if you just rolled out of bed and found something lying on the floor to wear.
God, you would loathe me then. I dress comfortably, I'm not out to impress anyone with my clothing or matching skills. My wit is impressive enough.