The following things are proven to make you happier (and smarter!). I try to do all of them.

1) Exercise for at least 60 minutes/day. I recommend getting a pedometer and walking 12,000 steps/day, plus working out with weights 2-4 times/week 2) Gratitude -- try to spend time every day thinking about the things you are grateful for 3) Meditation -- 10 minutes/day. It works. Studies prove it! 4) Relationship with the sun -- try to get outside at noon every day 5) Eat an anti inflammatory diet. Inflammation is heavily correlated with depression. 6) Try to do something nice for at least one person every day. 7) Research sleep quality and follow all the best practices. 8) Take a Vitamin D supplement, just in case :)

If you do all those things, you'll probably find yourself a lot happier at your job!