The next time you feel depressed, try this very simple technique. It also works equally well whenever you are angry or worried.
Laugh! That's all there is to the cure. Get away from other people so you won't feel embarrassed or get asked questions. Then laugh for 60 seconds. If you can find something humorous in your depressing (or upsetting, or concerning) situation, laugh about that.
If you can find absolutely nothing to laugh at, then just force yourself to go through the motions of laughing for 60 seconds. Just the physical activity of laughing will greatly decrease your depression, anger, and/or worry.
Try laughing for 60 seconds, and see whether you don't feel much better afterward.
Another very effective technique is to put a smile on your face whenever you feel depressed, worried, or afraid. Even if you can find nothing to smile about, put your mouth into a smile position. Pretty soon your smile will begin to feel genuine, and you will begin feeling better about your life.
Forcing yourself to laugh or smile isn't just a pretense. Laughing and smiling really do cause physiological changes: your muscles relax, your blood pressure decreases, and your hormone levels change - higher endorphin levels and lower stress hormone levels.