How to smile more often
How I did it: The key is to change your view point - don't regret but do give thanks: for what you have, what you experience, and what you meet in life. If you notice how great it actually is, you'll be happy. So simple - it starts in one moment!
Lessons & tips: Start smiling as a try. You'll see it won't hurt. You'll also see it helps in many situations.
Resources: My own lips :).
Next step is, to smile more to strangers - encouraging them to enjoy life!