[amIblue?]

Focus now on making yourself the best possible college applicant that you can (specifically grades and extracurriculars), and the sorority stuff will follow. It's not too early to be learning about the different organizations and trying to find as many possible rec writers as you can for now. I wouldn't start asking them for recs, but develop a kind of checklist of who you know in what org, etc. Work on polishing your social and conversation skills. The conversations in recruitment parties can feel forced and uncomfortable at times; the better you are at small talk, the better you will be in recruitment and, quite frankly, social situations in general.

If you are looking at NPC, try not to get your heart set on any particular organization. When I was in high school, I knew without a doubt that I would be in X organization. I'd never known anyone who was a Kappa. Things work out the way they're supposed to.