The scrying glass is a dark concave surface of reflective material. One can easily be constructed by using the curved glass face of a clock and painting the convex side with glossy black paint. Once the paint has thoroughly dried, bathe the mirror in an herbal brew of rosemary, fennel, rue, vervain, ivy and walnut leaves (or bark). If you want to be truly traditional, pour some sea foam into the mixture.
To charge the glass, take a deep breath and then slowly exhale outward upon the potion. Do this three times. Remove the mirror from the potion and dry it off thoroughly. Prop the mirror up vertically, supported by two sturdy books or bookends to hold it in place. Hold you right hand out in front of you so that your palm is facing the convex side of the mirror. Then place the left palm facing the concave side, about three inches away from the glass surface. You are now ready to magnetize the mirror.
With the left hand, begin making a circular clockwise motion across the surface of the mirror. Do this for a few minutes and then repeatthis on the convex side of the mirror with your right hand. The opposite hand is always held still while the moving hand circulates. To use the scrying glass, simply employ the same techniques as described for the divination bowl.