Turn off: Obsession with image. You could call it snobbyness, or being too high maintenance. Ignorance. Arrogance.
My worst nightmare of a man works in a cube, drives a flashy car, spends his income on the latest electronic gadget just 'because', and has no real hobbies besides figuring out how to show the world how much money he can spend and flaunt. Oh- and his nails are always just a little too clean.

Turn on: Flannel. HAHAHAHAHHAHA Seriously though, POsitivity. Genuine friendliness. Strong hands that look like they've seen some work recently. An enthusiasm for life. A touch of hedonism, and the bit of extra pudge to go along with.
My ideal man would be a laid-back dude with a good head on his shoulders, who has nice friends who care about him, some hobby or activity that he gets really excited about, isn't above a little manual labor, has a quirky sense of humor and the intelligence to back it up, and likes my cooking.