Try a few and see which people you enjoy working with. You also want people who will (1) be happy paying you real money if you can reliably produce value, and

Try a few and see which people you enjoy working with. You also want people who will (1) be happy paying you real money if you can reliably produce value, and (2) be more or less content to let you be the expert as long as you're on the ball about producing value and communicating effectively. You do NOT want cases where people will complain that $20/mo is too expensive, or that a $3 business app doesn't have enough features. Once you pick an area or two that you have interest in, your first steps should be trying to track down and connect with people. Can you do that? If not, it's probably a bad domain for you. Then, customer development interviews. Learn about them before you work with them. Existing domain experience from previous stuff you've done in your career is a good starting point. Never worked around real estate agents but have intimate knowledge of how to sell construction companies? That should tell you something about where to look first. It's a matter of applying conditional probabilities, really. Want to work with barber shops but find that's too general? Okay, what about hipster barber shop owners in their early 30s with a master's degree in English Lit? Now it's suddenly way too specific. Somewhere between the two, you become the ONE person in the city who is right for THEM.