After cutting the glass according to the specifications, first wash the front and back sides with tap water, then coat the iron red powder with water on the side to be plated, and then wipe off the iron red powder after drying, and then wash it with water. Then a trace of stannous chloride solution is used to scrub the glass surface to be plated. After washing, the residual stannous chloride is washed away with water. Finally, rinse the glass with clean water (preferably distilled water). Put the washed glass on a horizontal wooden frame or wooden bar, take a part of silver solution and a part of reducing solution, mix and pour them on. The liquid medicine should not flow away. About 2 deciliter per square meter. When it gradually reacts on the glass to form a silver mirror, pour out the excess liquid medicine, rinse with water, and pour 10% gelatin to dry. After drying, a layer of iron red primer or other antirust paint liquid is applied on the surface to form a mirror.