Do you deal with customers and clients in person?
If so, get to know the triple nod.
No nodding = bored or disinterested
Too much nodding = impatient or overly agreeable
The Goldilocks of nodding - just right - is three, slow and deliberate nods. That signals your customer to keep going by showing that you are listening.
And if it’s a tough customer who’s upset, add a tilt. That adds empathy.