1. If she has iPod on, ask what she's listening to because you're bored with your playlist. Make fun of her shittier music choices, bond over shared tastes
2. If she doesn't, ask where her iPod IS because all the cool girls have one so they don't get hit on by random guys. AW SHIT look what's happened now
Regardless of how you start the interaction,
find out where she's getting off very quickly so you know how much time you have to chat her up. You want to make sure that you have enough time towards the end of your interaction to tell her you think she's cute and you guys should do X or Y together later in the week, and exchange numbers.