Research how people use technology. I have meetings with participants where I ask them to do specific tasks and to think aloud while doing so. I then ask them questions about their choices.
I take note of places where they got lost or didn’t know how to complete a task. I then interview a subset of additional participants.
I analyze all of the interviews and make note of trends and common problems. I then work with a designer to come up with ways of solving those issues.
Then the prototype is updated and I interview more participants again to see if the new changes help.
I’ve done this with everything from diabetes meters to in-car navigation to productivity software. The field I am in is called UX Research