Party, meet girls, watch movies at the theaters with your buddies or gf or go alone, dine out, read, write, visit extended families, and/or go to college.
I married when I was 25 but I did the party thing before that. I'm in my early 40's now and I'm starting a new chapter myself. The kids are growing and I've got ample time now to maybe return to school, get a job (but I don't have to), travel (with my husband of course), etc. There's so much I want to explore still.