While working as a promoter at my University campus (quite a few years ago!), I can promise you that your best options are:

- A popular facebook account
- Campus reps (usually attractive female students)
- Society/club presidents

For this to work, you'll find it much easier to start somewhere hyperlocal where you can physically get face-to-face with people. Once you've established strategies and processes, you can start scaling out locally. However, the promotions team I worked with *still* physically visit each University campus around the UK and Europe at least once a year to keep the relationships going with their regional managers.

It's not coincidence that Facebook started at Harvard, and it's where the founders attended...