You need to understand the value your service or product will deliver to user(s), which is not just money related. To probe for value you must be able to tell a story about your product or service that enables your interviewee to picture themselves using and enjoying it. If you have drawings or images that can help someone relate to your story that’s even better. The story should be about them, “Imagine yourself walking in this mall [sitting on this beach] …” So try to conduct your interviews near where the product or service will be used.

The answer to this big question of “how many customers” starts by figuring out the answer to several subsidiary questions. The first question is … How will potential customers even find you? You might have a great product or service but unless potential customers can find out about you then they will never be your customer. There are many ways they can find you. You can rent a store in a mall with lots of foot traffic, you can advertise, you can rent a booth at a convention where your customers congregate, you can hold special events, you can pay celebrities to mention you, you can pass out flyers, …

Situating yourself amidst strangers interested in your idea

Where do people think about or do the thing you want to help them do better? This is where you want to hang out. This could be a food court where everyone is on apps or a computer killing time and therefore interested in finding more interesting things to do. Or it could be a trade show where most people share an interest in certain products. On-line special interest groups work for testing digitally delivered services but you must be careful because you can’t know true identities and potential competitors could be lurking as they search for new ideas.

A persona is a detailed description of a type of customer you may want to serve. Instead of treating “all customers” as the same, you can improve profits and customer satisfaction by realizing that specific types of people or businesses have their own different needs, problems, and goals. Think of each persona as a character in a story. Think of their background, what they care about, what frustrates them, and what they’re looking for. This will help design your product, remove unimportant features, and target sales messaging that speaks directly to personas.