There are two great books that helped me do this. First, the Mom Test, it is very short, and it talks about what types of questions to ask and what types to av

There are two great books that helped me do this. First, the Mom Test, it is very short, and it talks about what types of questions to ask and what types to avoid. The main focus is avoiding the introduction of bias. You want good data you can work with. Second book is Running Lean. It has a great script that you can adapt to the industry you are targeting. It also gives pointers on conducting the interview. Together, these two short books will get you started.