Have you ever met someone with a dehydrated sense of humor?
Where you couldn't quite tell if they were joking or not because of their deadpanned face, which caused you to freeze up on your response. Should you laugh? Should you be offended? Inside you're asking yourself, "is this person serious?" In other words, there was some confusion.
However, once they get to know me they begin to loosen up a bit.
When you're speaking to an audience this is magnified. Our words may be communicating one thing, but our face may be telling an entirely different tale. And it just might be a story we don't want to tell.
But here's the thing, your facial expressions should absolutely match the story (words) that is coming out of your mouth.
Smiling of course is a no-brainer. I always advocate a smile over a frown—especially if you're nervous. It helps draw the audience in and it helps dissolve any nervous tension between you and the audience. Unfortunately, even that can be overdone.
You should match your facial expressions to the emotional level that you and your words are trying to present. The best advice for how to achieve this? Be yourself. How would you normally react to a particular situation in real life? That's a good starting point.
But remember, if your emotions are too straight-faced, you could have a problem on your hands (or face). You might have to dramatize them a bit so that they resonate with the audience.
If they don't match, you risk losing authenticity and you might even look like a nut-job if you do that bit about your dog getting destroyed.
Bottom line: Reliving a frightening story? Look frightened. Recounting the day you got your dirty dog fluffy? Appear excited.
Keep the consistency and you'll avoid confusing your audience.
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