Ask HN: Tech people who are self employed. How do you do it?

I have realized that I love building software, and I suck at marketing. I'm trying to escape waged job, and switch to being self employed with more flexible times. I don't mind working long hours, but I have problem with 9-5, and being a wage worker.

However, as a techy, I can't seem to build useful things, or things that generate money.

Are there any tech oriented people who were able to quit wage work and turn into self employed? What did you do to achieve this?