Plexiglass is a heavy duty, plastic material that can have a clear or coloured appearance. It's commonly used for signs, aquariums, picture frames and displays. Since this has a nonporous material, you must first clean, prepare and use primer on the surface if you want any kind of paint to stick. Only certain kinds of paint will work with Plexiglass.
The Plexiglass surface must be cleaned to begin. Oil, dirt and debris will prevent primer and paint from adhering properly. Clean the surface with a mild soap and water. Place this mixture in a bucket and use a sponge to wipe down the surface.
Prepare the Plexiglass surface. Otherwise, you will not have a good working surface for the paint to stick to. Use 200-grit sandpaper or steel wool to lightly scratch the surface. After you have scratched the entire surface, wash it with soap and water. Dry thoroughly.
Choose a primer that works on plastic surfaces. Thoroughly read the product instructions before applying it. A spray kind, such as Rustoleum or Plast-kote, will work well. Allow the primer to dry according to the instructions. Primer is a vital part of painting Plexiglass as it gives paint the proper surface to stick to. Always work in a well ventilated area with plenty of dust sheets handy when priming and painting.
A water-based latex paint for Plexiglass works best. Oil-based paint will melt the plastic. Apply the chosen latex paint with a brush or paint roller. Allow the paint to dry thoroughly between coats. This will usually take around two hours. There are several brands on the market to choose from, and you can find a wide selection at home improvement and paint stores.
Another painting alternative is an acrylic spray enamel paint. Read the instructions of your chosen product before applying. Make sure the area is well ventilated. Wear a safety mask with spray paints so you don't inhale the fumes or paint particles.