Walk the entire surface to identify any cracks, potholes, or other damage. Note any areas needing repair before sealcoating.

Remove all debris, dirt, and loose material using a broom or leaf blower.
For oil stains, use a degreaser or a specialized cleaner to ensure proper adhesion of the sealant.
Pressure wash the surface to remove any remaining dirt and debris. Allow the surface to dry completely, which may take a day or more depending on weather conditions.

Trim any grass, weeds, or bushes encroaching onto the edges of the driveway or parking lot to ensure a clean working area and clear boundaries.

Use an asphalt crack filler to fill in any cracks. Follow the product instructions for best results.
For potholes, clean out any debris and fill them with an asphalt patching compound. Tamp down the material to ensure it's compact and level with the surrounding surface.
Allow sufficient drying or curing time for the repair materials as specified by the manufacturer.

Use an edging tool or a flat shovel to clean up the edges, removing any loose asphalt and defining a clear boundary.

Select a high-quality asphalt sealant suitable for your specific application, whether it’s a driveway or parking lot. There are different types of sealants, including coal tar and asphalt emulsions, each with their own benefits.

Thoroughly mix the sealant according to the manufacturer’s instructions. This often involves stirring the product to achieve a consistent texture and ensuring any settled materials are evenly distributed.

Equip yourself with the appropriate tools such as a squeegee, brush, or spray system, depending on the product and your personal preference.

Pour a small amount of sealant onto the asphalt starting from the highest point of the driveway or parking lot.
Spread the sealant evenly with a squeegee or brush, working it into the asphalt. Apply the sealant in thin, even layers to avoid puddling.
Continue this process, working in sections, until the entire surface is covered. Ensure even coverage and avoid leaving thick spots which can lead to uneven drying and potential peeling.

Use a brush to apply sealant to edges and corners where the squeegee might not reach effectively.

Allow the sealant to dry according to the manufacturer's instructions. This can take from 24 to 48 hours, depending on weather conditions and the type of sealant used.
Protect the surface from traffic, including foot traffic and vehicles, during this drying period by placing barriers or caution tape around the area.

Once the sealant is fully dry, inspect the surface for any missed spots or uneven areas. Touch up as necessary.

Keep the surface clean by regularly sweeping away debris and hosing down the surface to remove dirt and grime.

Plan to reseal the asphalt every 2 to 3 years, depending on the wear and tear and local climate conditions, to maintain its protective layer and appearance.

Promptly repair any new cracks or potholes to prevent them from worsening and to maintain the integrity of the sealed surface.