Yin characteristics: -(death or night) negative
The Yin man may let his body become portly. He's usually of medium height and might be rather muscular. Not many health problems, but he still doesn't smile much. Perhaps he's engaged in serious thought for he is rather introspective and realizes that from his prospective he's at the center of his universe.
His environment does have its effects upon him. Not exactly unstable with his feelings and moods, but very close. His confidence in himself keeps his emotions within bounds. Failure is something that may cause fear, but doesn't get in the way of a very active life. Uses a pragmatic approach to problem solving.
These people would work well in communes or in an Israeli kibbutz. They are more political in their thinking and are interested in success and safety or protection for their family and any group they identify with such as their country. They are serious in demeanor (no smiling idiots here) and usually more materialistic than not. Yin is an active individual and loves the company of others. Works for the good of the group.
Yang characteristics: +(birth or day)positive
The opposite of the above would make the yang people more self-directed and more comfortable operating by him/herself. They see no harm in wearing a happy face, but have little need to protect themselves by hiding in the center of family or group. They will stand alone and do not mind standing out from the crowd. Perhaps this is why they see dress as a costume to enjoy. Looking within means they are interested in their own self-development and may be given to meditation.
More the book lover than a yin person, they glory in nature, music, and even working with plants. Not exactly unsociable, but prone in that direction, their strength comes from within themselves and it may seem to others that they don't need family or friends.
Often lean and lanky they are enamered by colorful clothes and environments. With a smiling face he prefers to make life easy for himself and usually his life works. May be a loner since he is rather independent and with good intelligence. Rather commune with nature than battle the crowds. Where as the Yin man may find his success from the treatment of others, the Yang man seeks it within himself.