Remove furniture from the work area. If you are painting corkboard on the wall, place drop cloths on the floors below for protection against paint sprinkles.
Sand the cork by hand using a folded sheet of 220-grit sand paper. Use an electric sander for sanding large areas. Remove sanding dust with a tack cloth or a damp rag.
Dump paint sealer into an empty five gallon bucket. Thoroughly stir the sealer with a stir stick. Oil based sealer, or shellac, works best for sealing cork wood, but you can also use a latex primer.
Dip a 3/4-inch paint roller into the bucket of sealer. The thicker nap on a 3/4-inch roller works best for textured cork surfaces. Roll the sealer over the cork, while applying pressure, to push the sealer into the holes and crevices. Allow the sealer to completely dry.
Fill another empty bucket with latex paint. If you are painting cork floor tiles, it is recommended you buy quality floor paint for maximum durability. Use latex wall paint for painting a corkboard on the wall. Stir the paint thoroughly before application.
Dunk a clean 3/4-inch paint roller into the paint bucket. Apply the paint until achieving a uniform surface over the cork. Allow the paint to completely dry before applying a second coat.