Wash the shutters with warm water, a sponge and a several drops of liquid dish soap. This removes any dirt or dust from the vinyl, which helps the reinforcements bond more effectively with the vinyl. Let the shutters dry fully before continuing.
Apply epoxy to any cracks in the shutters to help seal them and reinforce the area against further damage. The epoxy should dry within a few minutes.
Paint the shutters with an acrylic latex paint to add another layer of protection to the vinyl surface. In addition, the paint freshens the look of the shutters if you want to use them for decorative effect. Vinyl expands and contracts significantly due to temperature changes, and the acrylic latex paint allows the vinyl to do this freely while other paints would suffer damage.
Apply vinyl tape to the inside of the shutters to reinforce them against opening. This prevents pets or children from pushing the shutters open while you're sleeping because the tape holds the shutters together as one unit while they're closed.