It is recommended that concrete pavers weather for a minimum of 3 months before sealing. This will allow the efflorescence (whitish salt) to rise to the surface before cleaning. First, remove all stains with the proper cleaning agents. These include a dirt and grease remover, a rust remover, and a paint, tar, and rubber remover. Next use efflorescence cleaner to dissolve efflorescence and remove ground in dirt on the entire surface. Power-washing will help to loosen and wash away dirt from the patio. Let the area to be sealed dry completely. Finally, protect the surface by applying either a wet look or natural look protective sealant. A roller is usually the easiest way to apply the sealant.