Any tips?

[twinstars]

That all really depends on campus atmosphere. If you are one of the only girls on campus with a nose piercing, yes, the sororities will take note of that. You'll be "the girl with the pierced nose" to all the sisters who can't remember your name during rush week. Maybe you are ok with that, maybe not. Don't change who you are, but if you think it's ok I think it would be smart to take the piercing out during rush week. It's not going to help your chances, and some sorority girls might think it's weird or that you're weird. And after all, it's just an accessory. You probably wouldn't wear it to a job interview, so you probably shouldn't wear it to rush.

About smoking cigarettes... during rush no one will know if you do or not. There are smokers in sororities, but how many depends on the house and the school. I don't see that being an issue during formal rush week. It's not like you'd be lighting up cigarettes during the rush parties or anything.