Boost your mood: Gratitude, gratitude, gratitude!!
Do you often feel like your days are tough and you cannot get out of a funk? Every day is "bad" and you are struggling to find the good? With all the research I've done through books, videos, etc, I have found the most common helpful strategy to stay positive is to practice gratitude daily. And heck, if you are religious, writing your blessings daily!
Getting in the habit of practicing gratitude daily helps the brain begin scanning for positive situations / things instead of always searching for the negative. While it seems simple, people often avoid this or put it on the back burner from what I've found. I also have found that at the end of your day, write one positive situation or thing that made you very happy, helping you mentally experience that positive joyous moment for the second time. Maybe your day isn't as bad as you think. I am including a the video below for a very informative TED talk that is only 9 minutes long, that provides some interesting info on how to get "unstuck".
So my suggestion is...find a fun journal or notebook and write 3 things your grateful for daily in the morning. Sometimes if I forget, I write it in my phone and then write it later in my notebook. Before bed, I write one positive thing that happened to me.
The link is as well: https://www.youtube.com/watch?v=7XFLTDQ4JMk