The psychological strategies of poker are a very interesting process and a much sought after ability when playing the game. The main thing to focus on is not to give your game away. In addition, if the player can read subtle body language signs, he or she may have more clues as to what kind of hand their opponent is holding. Novice poker players tend to give away their hand by shifting in their seat or looking glum/worried when they believe their opponents have better cards, however, the more accomplished player can skirt over this issue by seeming quite nonchalant about whatever is thrown at them.
Psychologically, it would be beneficial for the player to be more confident and look other players in the eye, maybe smiling as they did so. This confidence would unnerve the opposition, thus increasing the chances of winning. Another very good psychological trick when playing poker is to look bored– but do not go over the top. Creating a guise of boredom indicates that you know you have won the hand and keep quiet. There is no more of a dead cert giveaway than the voice.