Time with users is precious so you have to make the most of it. You should definitely allow room for spontaneous user-guided conversations, but you should never abandon your responsibility to prepare for interviews. Especially when following up with users (after testing), it’s essential to plan your discussions ahead of time. You may not get to every question you prepare, but you should come in with a plan for engagement.
How to prepare for an interview
Write down as many potential questions as your team can generate. Build on each other’s ideas to flesh out meaningful subject areas.
Identify and order themes
Identify themes or subject areas into which most questions fall. Then, determine the order of questions that will allow the conversation to flow most fluidly. This will decrease the potential for a scattershot interaction with users.
Once you’ve grouped your questions, you may find redundancies, or questions that seem strangely out of place. Cut them. Also, be sure to include plenty of “why?” questions, plenty of “tell me about the last time you _______?” questions, and plenty of questions directed at how the user FEELS. Remember, open ended questions allow for stories and stories lead to insights for design solutions.
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