How to Stain Existing Concrete

Clean the surface of the concrete. Use a push broom to remove all dirt and debris. Once you have cleared the area, rinse it down using a garden sprayer hose set on the highest setting possible. You can also use a pressure washer for this step. Finally, use the degreaser and a scrub brush to scrub off any grease and oil spots. By the time you are done, your concrete should be pristine.

Cover the grass, stone and landscaping around your concrete area with the sheets of plastic. If you get stain on any of these things, they will be permanently marked and the stain will kill your grass and shrubbery.

Let the concrete dry completely. This may take a full day. It must be completely dry before you move on.

Fill the spray applicator with a premixed stain. All parts of the stain sprayer must be made of plastic. Fill the tank about half to two-thirds full. Apply the stain from about 2 feet away from the concrete surface using even, sweeping motions. Different types of looks require different motions. For example, a stone look will be mottled, which means that the first coat should be even and heavy, but subsequent coats will be uneven in application.

Let the first application dry completely. Keep everyone and everything off the concrete during this time. It may take as long as 24 hours to dry if the weather is humid.

Apply subsequent coats of stain as necessary. If you are happy with your first application, then you can stop staining. However, uneven coats with "grains" (sweeps in similar diagonal directions) can give the concrete a look reminiscent of polished stone. Once you have finished each coat, allow it to dry fully before starting another. The final coat should sit for 24 hours, whether it is dry before then or not.

Roll on sealer with a paint roller. Use a roller with as little nap as possible so that you do not also seal "fuzzies" into the concrete. Cover every inch of the stained concrete to protect it from weathering. Once the seal has dried, you can start using your concrete.