27:19 (Y. Ali) So he smiled, amused at her speech; and he said: “O my Lord! so order me that I may be grateful for Thy favours, which thou hast bestowed on me and on my parents, and that I may work the righteousness that will please Thee: And admit me, by Thy Grace, to the ranks of Thy righteous Servants.”

The Prophet Muhammad (peace be upon him) said: Your smile for your brother is charity.” – Fiqh-us-Sunnah, Volume 3, Number 98

Narrated ‘Aisha I never saw the Prophet laughing to an extent that one could see his palate, but he always used to smile only. Bukhari 008.073.114

Senyum(Smile) – by Raihan

Action plan:

1. Practise good dental hygiene – Use a miswak/toothbrush.

2.  Smile with your eyes. the eyes are more essential to a warm, genuine smile.  To get a feel for how to make your eyes smile, get in front of a mirror and practice smiling, but concentrate only on your eyes. You may find it helpful to cover the lower part of your face with a piece of paper. Play around with it a bit, and you’ll find that you can make your mouth smile when your eyes aren’t smiling, and you can also smile only with your eyes. When your eyes do smile, remember how it feels, which muscles are working and how. With practice, you’ll be able to smile with your eyes at will.

http://www.wikihow.com/Smile

Benefits of smiling
1. Smiling changes our moods
Next time you are feeling down, try putting on a smile. There’s a good chance you mood will change for the better. Smiling can trick the body into helping you change your mood.

2. Smiling Is Contagious
When someone is smiling they lighten up the room, change the moods of others, and make things happier. A smiling person brings happiness with them. Smile lots and you will draw people to you.

3. Smiling Relieves Stress
Stress can really show up in our faces. Smiling helps to prevent us from looking tired, worn down, and overwhelmed. When you are stressed, take time to put on a smile. The stress should be reduced and you’ll be better able to take action.

4. Smiling Boosts Your Immune System
Smiling helps the immune system to work better. When you smile, immune function improves possibly because you are more relaxed. Prevent the flu and colds by smiling.

5. Smiling Releases Endorphins, Natural Pain Killers and Serotonin
Studies have shown that smiling releases endorphins, natural pain killers, and serotonin. Together these three make us feel good. Smiling is a natural drug.

From article: reasons to smile

NB:  Always remember when doing a good deed, have the correct intention/niyyah, do it for Allah’s pleasure with sincerity.  May all our good deeds be accepted. InshaAllah.