There are many things that we do not have much control in our life, but we do have total control over how we think and respond to them. Our mind is a great instrument and regardless of the environment, rational thinking always lead us to inner peace.
They key is to embrace this thing you fear most. Once you have accepted the uncertainty, the unknown, or failure, they will no longer have a hold on you.
Your mind is your ally, and your breath is your body's remote control.