Arms crossed across the chest is one of the most powerful and basic gestures used by anyone. One can form a barrier between himself and another person by crossing his arms, or it may simply mean that he feels cold. It can also indicate as a protection or defense in nervous or anxious situations.
When you are talking to someone and he would cross his arms, it means that he opposes, suspects, or doubts what you are saying. But if he is talking with his arms crossed, it means that he may be nervous, lying, or hiding something from you.
The pockets are never the right place to put your hands into. A person with his hands in the pocket may indicate that he is nervous, uncomfortable, bored, or uninterested. This gesture indicates also that he may be hiding something from you or he doesn't want to engage in a specific activity or task.
An open palm means sincerity or honesty. A clenched fist is a very clear indication of frustration, anger, resistance, and defense. But there are times wherein it indicates confidence in one's idea or opinion. Nervousness or anxiousness is seen in someone who is tapping or twitching his fingers. Rubbing of hands, meanwhile, may indicate extreme excitement or cold feeling.
Read another person by reading his body language. One's actions definitely have more honesty compared to the words coming out from his mouth.