Sweat? Hell, thats the least of my worries. I just try to dress accordingly and wear breathable clothes.

Sometimes you get the "look" when you walk into an office, but you'll probably get it whether you're soaked in sweat or not. The people calling you for a pick up will do it whether it's 75 and sunny or below zero and snowing, and they know you're on a bike most of the time, so they don't expect "much" from your appearance.