I think what you're really asking is how to act around women you find attractive. Beauty is different for different people.

I think if you are healthy you act the same around all people. If theres a woman you want to ask out, it would be considered normal to pay her a little more attention than someone you wouldnt want to ask out. Pull out her chair for her or make yourself available by being near her in some way. Dont be creepy about it.