Most people I put in front of a camera for brand testimonials and interviews have never done this before, and the standard directing advice built for working actors doesn't translate well to someone whose main goal is just not looking terrified. A few things that have consistently made non-actors look natural rather than stiff.
Never give them the exact words
Scripted lines from a non-actor almost always read as scripted, a specific cadence and eye pattern that betrays memorization even when the words themselves sound fine. I give people the idea of what to say, the key points a client needs covered, and let them find their own words in the moment. It takes more takes to get a clean, complete answer this way, and every single one of those takes sounds like an actual person talking rather than a person performing a script.
Interview them, don't direct them, for the first few takes
Starting with genuine conversational questions rather than "and action" formality gets people talking naturally before they've had time to get self-conscious about being filmed. I usually roll camera during what the subject thinks is just a pre-interview chat, and some of the best usable footage comes from that period specifically because nobody's performing yet.
- Give subjects the idea, not the exact words, every time
- Roll camera during the "warm-up" conversation, not just the formal take
- Ask questions that require genuine thought, not yes-or-no answers
What to do when someone's genuinely stuck
When a subject freezes or keeps giving flat, one-word answers, I've learned that pushing for a better take rarely helps and usually makes the anxiety worse. Switching to a completely different, lower-stakes question, something personal and unrelated to the actual pitch, often relaxes someone enough that the next attempt at the real question comes out naturally. Small pivot, and it's rescued more than a few testimonials that were heading toward unusable.