How to laugh loudly?

I heard this sentence from lots of body: I smile a lot but I rarely laugh deeply, I don't feel them heartily since my my childhood. It's even better than many people that are depressed and feel bored. Meanwhile even there are many people watch funny movies but they just have a small smile but what's the problem??? Here I explain them to you and try to find a solution and I hope that readers of this post give their experiences and suggestion.
Somebody are deeply in their problems and believe that they are a miserable one, step by step they believe it by every molecule of their body... the other reason is our sins, sins make us more cruel. I believe below mentioned solution can help us to have a better life and for laughing heartily. 
1- Don't forget the great GOD and believe that your problems are too small in compare with his great power.
2- Try to be a better one for your society and even for the world.
3- Try to do more social activities. "watching funny movies, telling jokes,.."
4- Everyday is great don't lose your great time by thinking to bad things.
5- Write funny comments about your family's photos.
6- Forgive others and forget revenge.
7- Find an appropriate time for laughing
8- Check funny post of www.restland.blogspot.com