Children have very obvious gestures but as we get older we learn to be less obvious.
Kids run behind the couch or Mum when they are scared or threatened, when they don't want to listen they cover their ears, when we say 'No' to them they cross their arms, chin down and turn it side to side. When they lie, they lose eye contact, hands go to their face, mouths open, shoulders shrug.
As adults instead of running behind something we cross our arms, instead of covering our ears we might pull or rub our lobes, instead of looking down when we lie, we might glance down, chin might be down and finish off with a false cough.