What to do when SA recruiting is done?

I was extremely fortunate to land a BB SA offer for summer 2018. However, now that recruiting is done, I'm feeling a bit lost. I feel like I've dedicated the entirety of my college career to landing an investment banking offer, and now that I've accepted the offer, I don't know what to do with myself.

How should I spend the rest of the fall and spring semesters? What activities can I do to keep myself busy and productive?