What are the really small things that you do and they can tell a lot about your psychology and personality?

1- Taking a nap during meeting time.

2- Chewing a gum when meeting is still on.

3- Listening a co worker and thinking wasting time.

Smiling, and paying attentions to small detalis

Eye contact, body orientation, hand gestures. However, voice quality, voice tone and pitch. 

Thank you all for your replies gentlemen. I agree with you all in addition to many other things like your handshake, the way you sit down and sometimes even the way you drink from a cup.