The fingers cover the mouth
Cover or Shyness The hand shall hide is socially undesirable gestures such as yawns or giggles.
“Not everyone should see this.”
Insecurity The person is not sure about what he/she says.
“I can not guarantee that this is true.”
Covering the mouth is often used as an indicator for lies. This is mostly true for young children. When growing up, we learn to hide our uncertainty and to avoid this gesture.
Often the person feels obligated to say something, but would rather not. Then the answer is delayed.
Always remove your hand from the mouth when speaking.
This is one out of 63 gestures from the body language trainer.