Some options: 1) Do you have freelancing or other experience which has exposed you to multiple people with similar problems? For example, have you implemented the same "$()#% authentication system for a web application 20 times? Package up that one little piece of the puzzle into a scalable way to teach people to do it without needing to have you or someone similarly skilled on their team. Common form factors include…
As an aside to (2). You might not even need to go as far as creating and marketing a full SaaS. I know small businesses that are paying $100-$1000/month for small little services or manually doing tasks at similar costs. Automate/replace their stuff with some bespoke code and share the savings.
Example: not everyone wants to admit they have problems in their business, so you have to approach the conversation from an indirect angle.