Learn the rudiments of astronomy, so that you may identify stars and constellations in the night sky. Armed with such knowledge, venture to a place where the sky is clear and the stars are bright, and make a star chart on a piece of parchment. Mark all of the stars which seem brightest. Do this on the equinoxes and solstices of the same year, using the same chart each time.
Make a tall, conical hat from dark blue material. Around the base of the hat, embroider signs of the twelve constellations of the zodiac with silver thread. Around the remainder of the hat, embroider small silver stars in places of the brighter stars of the sky, as marked on your chart.
When the hat is completed, burn the star chart made with the parchment. Take its ashes and sprinkle them inside the hat, speaking a short incantation with words of power designed to let you see what shines behind the light of day.
Wearing the hat will allow access to a limited form of clairvoyance.