I don't really dress different for guys anymore. I really don't care. I will do it for myself. One of my jobs, I have to dress up a bit and I don't mind. But I don't do it for guys. I'm more feminine and dressy when I do go out, like a summer dress and a cute pair of heels. with a matching bag. I make sure my hair isn't all over the place and that's about it ;-)
Smile, but not too much. Enough to show movement in your lips and cheeks. Look at him/her with low and calm eyes. Slightly move your lips and cheeks in a sensual manner to show your attraction to him or her.
I don't think you should change the way you dress or your hair to get a guy to notice you. The right guy should notice you just the way you are. I think you can try to look the best by working with what you got, or clothes that are your style that might draw a little more attention. Like your favorite outfit that gives you a little extra boost in your step.