Did you notice how your mood can change if you begin to smile? In fact, smile is one of psychological mechanisms for improving your mood. No matter how bad you feel, the only thing you should do is to make yourself smile. At first you may feel silly but in some seconds you will be surprised to discover that your mood really becomes better!
So, my idea is to use this mechanism in the morning in order to provide a perfect mood for a whole day! When you wake up, do not get up from the bed at once. Lie for some minutes and try to imagine something pleasant, to remember some bright and captivating moments of your life. Strive to remember relevant situations in detail and feel those nice feelings afresh.
This easy and simple exercise won't take much of your time, but will imbue you with positive emotions for a whole day!