To make a softly reflective mirror, use glass from a picture frame or have a piece cut to fit a favorite frame. Silver leaf, sold in booklets of 3-by-3-inch squares, is easy to work with, but very delicate (1,000 stacked sheets equal the thickness of a nickel). Remember these tips: Work in a draft-free room; do not get silver-leaf booklet wet, and do not pick up silver leaf with your hands. You'll also need gelatin sheets, distilled water, two 1- or 2-inch brushes, a gilder's-tip brush, a No. 12 brush, cotton balls, and acrylic clear coat.