1. Invest
2. Play games
3. Mining
4. Gamble
And probably more things that i can't think off right now
Invest wisely, dont think investing is an easy task to earn bitcoins, same as gambling it has risks. I dont really get when you say playing games because playing games with bitcoin is considered gambling, unless it is a faucet. And the Op as what to do with bitcoin, not how to get bitcoin, so bitcoin is out of the list.
+1 all of those to use is risky, you will probably lose everything and even addict to that. as well, this is a form of the use if you wanna risk multiplying it.