Men are simple. Generally we look for hot women. You don't even have to be hot really. Just maintain yourself, have simple clean hair, put on a little makeup (not too much), wear something that fits nice, show a bit of femininity, put on some heels(definitely), carry yourself well...and show interest if you are interested... that works miracles.
And oh, I know you're not looking to attract men in that* way..... but really, that's the only thing men will respond very well to....haha. Seriously, men are more shallow than you might think.