To begin with, stop affirming your so-called headache is a headache.
Call it a so- called headache.
This initiates doubt for the subconscious that the pain is even really there.
Next, query yourself about it.
How big is it?
The size of a marble, golf ball or soft ball?
Does it throb?
Is the pain sharp or dull?
Point to where in your head you feel it, and bring your conscious awareness to the area.
Is it surface oriented or subsurface oriented?
Is it long or short?
Picture in your mind its appearance.
Does it have a color?
Is it hollow or solid?
Let your answers be what first comes to your mind.
Where is the so-called headache now?
Continue visualizing and describing the so-called headache until it vanishes.
Preoccupation with these mental questions and answers takes the mind off the tension which brought about your head pain.
Whether it is vasodilation or vasoconstriction of the cranial blood vessels, just shifting your conscious awareness to the pain area brings about a more normalized blood flow, and touching the spot helps to orient your conscious awareness as to its location.