Its AdSense which is not YouTube exclusive. Other than building your channel, you can do what I used to do which is create niche websites that are heavy in uniquely written content and seo them. Lots of people get small niche sites ranked well in Google and make some money with it. The more sites you have, the more you will make. But that all takes a lot of time, just like building a channel. No easy or fast way to make that happen.