Epoxy is a two-part resin that can be used to fill holes and cracks in surfaces. It is strong and durable, making it ideal for repairing damage in high-traffic areas. To mix epoxy, equal parts of the resin and hardener are combined until they are fully mixed. The mixture is then applied to the surface using a putty knife or similar tool. Once the epoxy has cured, it can be sanded and painted to match the surrounding area.