Clean your RV. Wash the exterior of your recreational vehicle thoroughly with soap solution and a sponge or brush. Make the soap solution by combining liquid dish soap or soap powder with hot water in a bucket. Wash your RV from the roof down with the brush so gravity helps the dirt flow away. Don't forget to clean the roof, which can collect dust and dirt that will run down the sides of your vehicle and spoil the paint job. Wash and rinse your vehicle until no dirt remains. Leave your RV to air dry completely, which may take a few days.
Check the RV for scratches and holes in the existing paint job and fill them in before you paint your RV. To patch scratches and holes, use a body filler and sand off the excess with fine sandpaper so that the surface is smooth. A smooth surface makes a good base for your new paint. Remove any flakes of old paint that can create bubbles under the new paint if they remain.
Apply tape to cover the areas on your RV you don't want to paint. These include the edges of the windows, the lights and the metallic trims on your RV. For larger nonpainted areas, use a combination of paper and tape to cover.
Apply primer all over your RV. Tim Carter from "Ask The Builder" suggests using a thinned down oil- based metal priming paint in proportions of one pint of paint thinner to one gallon of oil-based primer. Try using a paint sprayer to conveniently apply the primer and work over the vehicle in broad strokes for an even finish. Apply another coat of primer. Leave the primer to dry for the recommended time on the label.
Paint your RV. Paint within 48 hours of applying the final coat of primer but leave enough time for it to dry completely. Apply the finish coat of an acrylic latex paint in your preferred shade. There are many different paints available from a number of manufacturers that are designed for your RV. Work your way from the top of your RV downwards, using several broad, thin strokes. Use a roller or a paint sprayer to apply the paint to your RV.
Dry your RV. Wait for the first coat of paint on your RV to dry before adding another coat, using the same process. Let the second coat of paint dry thoroughly before you move the RV.
