Go outside half naked in the snow...
and meditate. Think about creating the perfect flame. Picture a small flame burning in your heart, then slowly move to your whole body being on fire. See how long you can last in the snow, without freezing your ass off.
It helps to take deep breaths.
I against I,
flesh of my flesh,
and mind of my mind,
two of a kind but one won't survive,
my images reflect in the enemies eye,
and his images reflect in mine the same time,