At first sight, its the looks. We can't know how someone's personality or how intelligent they are from looking at them. I've been saying this for a while: We come for the looks, and we stay for the personality. I'm pretty sure that's how everyone works.
I usually notice a girls looks first, I think that's a given as you do need some kind of visual click. Yet I'm also not shallow and will give any girl a chance as after awhile the personality will be the one you truly fall for. I mean hey, you can date the sexiest girl alive but if she's a completely stuck-up girl, won't go far.
its tough at first you just get a simple look at them so there general appearance is what you notice , if you get a chance to talk to them you start to get a feel for there personality , but at first its very tough , you sort of just go for the girls you like for whatever reasons . maybe they were cute or something .