Mirrors reflect light in your home, so the rooms look and feel bigger. Some homeowners decorate their mirrors by painting designs and patterns on the mirror to dress it up while still allowing light to project in the room. Not all types of paint can be used on a mirror, but you don't always have to purchase glass paints to get the painted look on your mirrors.
Glass paints are paints that are made specifically for glass and mirrors. The mirror does not need sanding or roughing up before the paint is applied. You can apply most of these paints with a paintbrush. Most types of glass paints will require that you heat the glass for the paint to adhere permanently. While some paints require a kiln, most glass paints that are purchased at a craft store can be heated in your oven. Place the glass in the oven while it is still cool and let the glass heat and cool with the oven. Bake per the manufacturer directions of the glass paint. If you're mirror is too big for the oven, try another method.
Oil and Acrylic Paints
Both oil and acrylic paints can be purchased at craft stores. These types of paint are not specifically made for the glass on a mirror, but will stick when the mirror is properly prepared. Lightly sand, or sandblast the mirror to prepare it for the paint. This will rough up the surface and get the mirror ready for the paint. Clean the mirror with rubbing alcohol or glass cleaner to remove any grease or dirt on the mirror. Apply the oil or acrylic paint and let the paint dry for as long as the manufacturer recommends.
Model and Automobile Paints
Similar to oil or acrylic paints, model and automobile paints are easy to find and purchase. Because of their availability, they can be purchased in a wide variety of colours. You can heat model or automobile paints in a kiln or oven to make them stick to the mirror better, but you do not need to. Additionally, like oil and acrylic paints the mirror must be properly prepared for the paint to stick. If you don't prepare the mirror, the paint may flake or peel from the mirror.
Spray paint is another great paint option for the glass on mirrors. Spray paint is relatively inexpensive compared to other types of paint that can be applied on glass. Before applying the paint, rough up the surface with sandpaper. Use glass cleaner to remove dirt and dust from the sanding. Because glass expands and contracts, you will want to apply a painting primer on the glass prior to the paint application. Hold the primer 12 inches away from the mirror and apply it in a few light coats. Let the primer dry and then repeat with the spray paint.