You've got a long life ahead
of you and I'm sure you'll think of some interesting ideas over time.
The key is to just keep playing...don't give it up for anything (school, girlfriends, wives, kids, career, etc.).
Probably the best and easiest thing you can do is start playing with other musicians...form a band, you'll be in lots of them over the years if you stick with it. There are plenty of people playing instruments and they (or you) don't have to be experts to get together and have fun playing music.
In high school I was in three bands in one night at the school talent show (they ended up changing it to a battle of the bands after that). Nowdays I juggle five different bands...hard to get bored that way.
I went and recorded my own percussion CD and set up my own label for it...that's another avenue. But even with a well recorded CD complete with professional packaging, etc. and getting it listed all over the internet through music sites and such, you probably won't get much response to it...no one buys mine.
It boils down to coming up with ideas and trying different stuff but continually working with other musicians to keep you in the game. Eventually you may find that it's become a business....even if it's part time.