Properly cared for, an asphalt driveway will last for many years. To get the most out of your driveway, timely preventative maintenance is vital, and one of the most important parts of a regular maintenance program is top coating, or sealing, the driveway on a yearly basis. Top coating might take a little time, but when properly done it helps prevent water from working its way into and underneath the asphalt, one of the main reasons for driveway decay.
Pick a day that's forecast to be dry and warm. The topcoat won't adhere well to the asphalt if the surface is wet or cold.
Patch any large cracks in the asphalt with an asphalt patching mixture. You can get this, premixed in handy application bottles, at home improvement stores. Fill the crack with the patching mixture and let it set according to the mixture's directions. Larger cracks may take more than one application to fill properly.
Wash the driveway with a hose and pressure nozzle. If you have access to a pressure washer, you might consider using it for a deeper clean. Let the driveway dry completely before proceeding.
Spread the top coat sealant with a stiff brush on a broomstick or a roller on a broomstick. Pour a little bit of sealant out of the bucket, spread it with the brush or roller until you have an even coat, and then proceed to the next area. Work backwards, so that you don't walk over the areas you've already done.
Block off the driveway to prevent inadvertent use, and then let the top coat dry thoroughly before walking on it or putting a car in the driveway. Usually 24 hours of warm, dry weather is enough time for proper curing.