Doing a customer interview is one of the most efficient ways to gain insight to develop your product or the way you market it.
You book an appointment to meet a customer for 30 - 60 minutes, preferably not someone you know already but who would represent a real potential buyer of your product or service. The purpose of the interview is to try and understand if the problem you are trying to solve with your product is a problem the customer actually has. That's the problem validation or problem finding part of the interview. You also want to gain useful insight into how the customer buys your kinds of products or services, and how you can fit in with that (or improve that experience for them), and then talking pricing. A bonus is if you actually get an order, but that certainly isn't the point.
Following are two useful documents to help you get going on your first customer interviews.
Download the homework sheet for this assignment. The questions from this