How do I get her to be my girlfriend?

This girl I know from my school have been getting pretty close. Before our winter break we chatted only a little, but after break started we've basically been texting everyday all day (She lives in Cali I live in Chicago). We have shared some cute dialogue like "goodnight beautiful" and "what's cookin good lookin" and it seems like we both like each other. So my question is when we both go back to school and we see each other how do I take it to the next level (like a relationship)? I really like her and was hoping to develop something but was a little confused on how to get there.