Remove any decals from the side of the boat before painting. To remove them, apply the heat from a hair dryer and then scrape the decals off with a utility knife.
Wash the entire surface of the boat that is to be painted with soap and water. This will remove any dirt and wax from the surface of the boat which prevents the paint from adhering properly. Apply a grease remover to the surface of the boat to remove any remaining bits of grease or wax. You might have to clean the surface of the boat several times to get it ready to be painted.
Tape the edges of the boat with painter's tape and cover the entire deck surface with clear plastic bags. Secure them in place with masking tape along the entire perimeter of the deck.
Sand the surface of the gelcoat with a handheld sander---the more people you have doing this, the quicker it will be to sand a large area. If the gelcoat is in rough shape, use a heavier sanding grit such as 80. If you notice and cracks or holes, repair them as you complete the sanding process.
Apply a layer of primer over the entire surface of the boat using foam rollers to speed up the process. Roll vertically to cover large areas of the boa. You will need to apply enough coats so that you cannot see the color of the original gelcoat.
Allow the primer to dry and apply your final gelcoat, using the same technique you used to apply the primer. Wait at least an hour before you remove the painter's tape and reveal the floor and other surfaces.
