What I do (and would recommend) is building an adjacent product and selling it. The product could be just a higher quality version of the content (e.g. book, c

What I do (and would recommend) is building an adjacent product and selling it. The product could be just a higher quality version of the content (e.g. book, course, etc.), or it could be something in the space, like a SaaS that helps your audience solve a problem the blog talks about. This is a good way to upsell the people willing to pay without upsetting any of your readers. Also, positioning it as a different product breaks the "blogs should be free" mental block many people have.