How do you get college students to sign up for your exlusive blogging app?

Hey, I just released https://wiredclan.com, exlusively for tech students. I do have access to my college's network so I have a few initial users but how do I reach out to other colleges? Here's what I've come up with so far: Find college tech groups on Facebook (and spam there?). Ask my sister who's in college. ??? Appreciate your inputs here. Thanks!