Practical and neat.
If it looks like you spent an hour and $400 putting that outfit together, you'd better be taking my cute ass out for a nice dinner!
Otherwise, I dig a guy in work clothes... broken-in carhartts, boots, polarfleece, and a barn jacket... nice. Bonus if he's got sawdust stuck to him somewhere.
Other than that I have a thing for polo shirts.. nice ones, not the thin cheap type that grandpas wear, but the thick, heavy pique ones.
What I can't stand is that saggy ass jeans with the hat that looks like you just bought it 5 minutes ago, especially worn over a bandana... ??? is your head THAT cold?