Cheap aluminum spray paint, some use copper coat spray, but Ive had good luck with the aluminum spray paint and cleanup is easier I think. Just clean the gasket with lacquer thinner, lightly scrub with a scotch brite pad, anneal, then re-coat with paint. I start with 1/3 torque value, then 2/3, then full torque value. After a couple heat cycles it's good practice to retorque again. Key thing though, that your deck and head surfaces be true. Not as much forgiveness as a graphite gasket. Can lap those surfaces just to be sure.