The Moodscope site is a very useful tool for monitoring the quality of your mood. Awareness is a good step toward improvement. If you sign up for the free site, you can elect to have daily email reminding you to measure your mood. As a bonus, the email contains a short reflection designed to help you manage your mood.
Today my volunteer submission Life As Accomplished Marathon Runner was the emailed reflection. If you are into running or mental health, you might give it a look