Clean the surface carefully to remove all traces of paint, dirt, moisture or other substances.
Repair any cracks or holes in the concrete with hydraulic cement.
Seal the concrete with a masonry coating and let it dry completely.
Apply a coat of primer using a roller or sprayer and let it dry completely.
Apply a coat of paint using a roller or sprayer and let it dry completely.
Apply additional coats of paint as needed allowing each to dry completely between applications.
Apply a coat of sealer and let it dry completely.