There should be happiness from the beginning of the life. It has little value if you get it at the end of your life.
(J.Krishnamurti) 

If we only wished to be happy, it would be easy.
But we wish to be happier than other people which is always difficult.
Because we think them happier than they are.
(Charles De Montesquieu : 1689-1755) 

The secret art of inviting happiness
The miraculous medicine of all diseases
Just for today, do not anger
Just for today, do not worry
Just for today, be filled with gratitude
Just for today, devote yourself to your work
Just for today, be kind to people
Every morning and evening, join your hands in prayer
Pray these words to your heart
Chant these words with your mouth.
(Usui Mikao)