Contrary to popular assumption, being happy is not automatic. The Dalai Lama calls it an art. Martin Seligman, the man who gave us the concept of positive psychology, says that while 60% of happiness is down to genetics and our environment, the other 40% is up to us.
In other words, it depends on how we think and on the way we live our lives. It is just like your general heatlh -- you have to work at it and maintain it.
So what do generally happy people do to maintain their sunny outlook? Here are 12 key methods to put a smile on your face.