Are you a novice to the habit of smiling. I will suggest a beginning exercise that may help. Not only will you feel better, but it pays well too.

S – Stretch your cheeks as far as they can go to the left and the right.

M – Make yourself hold that position.

I – Inhale, but hold your facial position.

L – Lighten up your stance by tensing and relaxing your muscles.

E – Enjoy the giggle that is now turning from a chuckle to a cackle.

Practice this process until it comes naturally. Maintaining the habit will not be nearly as challenging as starting. Others will reinforce it by smiling back and you will feel like a million dollars.

he advantages to smiling are both documented and anecdotal. 

From Net Doctor.

From Lifehack.

From Fast Company: How Smiling Changes Your Brain.

From a research perspective, take a look at this paper: The Memory Promoting Effect of Smiling in Face Cognition.

Can it be that smiling makes us smarter too?