My best advice (in the short term) is to contribute to a huge open source project. At the depths of my boredom I contributed to dotnet, who better to learn from than the people who make your tools? Amazingly bright minds to learn from.

Contribute to React. Contribute to Boost. Contribute to Scala. What are you using, or what do you wish you could to use? Contribute to that.

And how do I get more money? Working for free?

Let me tell you a secret. A friend of mine is the no. 1 maintainer of a very popular OSS. 60k stars. He got paid way way way lesser than me.