Fellow college student here though I'm probably a little older than you. If you get the number early in the week try to hangout/close her before the weekend hits and she goes into party mode. What you're trying to avoid here is her getting distracted by some frat star or party animal she meets. It used to crack me up how many girls would come to the parties I threw straight from a date and end up going home with someone.
For girls in line I just play it cool and make small talk with the occasional light tease. When it's time to go I say "Let's hangout sometime." while handing her my phone.
I know you said you hate frat/house parties etc, but you are missing out on a major hunting ground. The party scene is one of the easiest places to get laid because all you have to do is show up and not get blackout drunk like most of your competition.
For girls in line I just play it cool and make small talk with the occasional light tease. When it's time to go I say "Let's hangout sometime." while handing her my phone.
I know you said you hate frat/house parties etc, but you are missing out on a major hunting ground. The party scene is one of the easiest places to get laid because all you have to do is show up and not get blackout drunk like most of your competition.