One of my favorite mantras

"I must not fear.
Fear is the mind killer.
Fear is the little death that brings total obliteration.
I will face my fear.
I will permit it to pass over me and through me.
And when it has gone past I will turn my inner eye to see it's path.
Where the fear has gone there will be nothing.
Only I will remain."

-From Frank Herbert's Dune

For some situations, it really helps.