So, how was the interviews? Haven't scheduled them yet? Why?

Try to use the questions you have defined to validate you certainties, suppositions and doubts.

While interviewing, take notes of the most relevant behaviors and feedbacks you saw during the interviews and after each interviews you made, try to synthesize some key insights!

If possible, try to take some pictures of the environment, objects, context of the users. It will help you to make more realistic moodboards about the users.