Here it is. Print it out. Repeat it often. (And I don't think it really matters if you a Christian or not to use the Psalms. I belive that they have been recited so often that the mere words themselves have built up power over the thousands of years that they've been around.) Give 'em a try.
The Lord is my Shepherd; I shall not want.
He maketh me to lie down in green pastures:
He leadeth me beside the still waters.
He restoreth my soul:
He leadeth me in the paths of righteousness for His name' sake.
Yea, though I walk through the valley of the shadow of death,
I will fear no evil: For thou art with me;
Thy rod and thy staff, they comfort me.
Thou preparest a table before me in the presence of mine enemies;
Thou annointest my head with oil; My cup runneth over.
Surely goodness and mercy shall follow me all the days of my life,
and I will dwell in the House of the Lord forever.