If you want to be happy, smile
There have been numerous studies conducted on the connection between smiling and happiness, and all of them have routinely found that when you smile you feel happy. “In 1989, a psychologist named Robert Zajonc published one of the most significant studies on the emotional effect of producing a smile.” Julia Layton writes in Does smiling make you happy, “The reason why Dr. Zajonc's research is so significant in the field is because he proposes a detailed, physiology-based explanation for the cause-and-effect relationship. According to his hypothesis, the facial changes involved in smiling have direct effects on certain brain activities associated with happiness.” Before Robert Zajonc, Charles Darwin proposed that our facial expressions not only reflect our emotions but cause them.
However, we have been conditioned to believe that we need to have something good happen to us for us to feel happy, it seems counterintuitive that an expression without a cause can make us feel the same emotion. Even though it might not make much sense to us, the research backs Darwin and Zajonc up. Multiple psychologists have proven over and over that if you smile you will feel as happy as if a positive event just occurred, that the bio-chemical reactions are the exact same whether you are "faking" the smile or it is genuine. This research, cuts out the middle man, it cuts out the need for an event that will make us smile.
Instead, we can reflect the emotions that we want to have and our bodies we follow suit. We don't need to have a great day in order to smile, in fact this suggests that we are more in control than we give ourselves credit. So, if nothing is going according to plan and you need a reliable way to elevate your mood and if you want to be happy, SMILE!