A little meditation to do morning and night.
First thing in the morning, imagine yourself tremendously happy. Get out of bed in a very happy mood — radiant, bubbling, expectant — as if something perfect, of infinite value, is going to happen today. Get out of the bed in a very positive and hopeful mood, with the feeling that this day is not going to be an ordinary day — that something exceptional, extraordinary, is waiting for you; something is very close by. Try and remember it again and again for the whole day. Within seven days you will see that your whole pattern, your whole style, your whole vibration, has changed.
When you go to sleep in the night, just imagine that you are falling into divine hands…as if existence is supporting you, that you are in its lap, falling asleep. Just visualize it and fall asleep. The one thing to carry is that you should go on imagining and let sleep come, so that the imagination enters into sleep; they are overlapping.
Don’t imagine any negative thing, because if people who have an imaginative capacity imagine negative things, they start happening. If you think that you are going to get ill, you will get ill. If you think that somebody is going to be rude to you, he will be. Your very imagination will create the situation.
So if a negative idea comes, immediately change it to a positive thought. Say no to it. Drop it immediately; throw it away.
Within a week you will start feeling that you are becoming very happy — for no reason at all.
Osho, The Passion for the Impossible, Ch 3
Credit to Magno