Turn on a wet/dry shop vacuum and use it to vacuum out the cracks within the concrete. This will remove all dirt and loose debris that could interfere with the repair.
Wash the inside and surrounding areas of the cracks with a pressure washer to remove any dirt, grime or grease. Use the wet/dry vacuum to suck away any standing water within the crack. Allow the concrete to dry.
Dip a small paintbrush into the concrete bonding adhesive, and apply a thin layer to the interior bottom and sides of the crack. Different concrete bonding adhesives may require diluting with water. The size of the paintbrush will depend upon the size of the crack. Choose a paintbrush that is small enough to fit all the way inside the concrete crack. Concrete bonding adhesives allow the self-leveling concrete to bond to the exposed surface of the crack, eliminating the risk of separation.
Allow the concrete bonding adhesive to dry for one to two hours. It may be sooner or later depending upon the size of the area.
Mix the self-leveling compound with water in a 5-gallon bucket, according to package instructions. Use a mixing paddle attached to a power drill to remove any lumps from the self-leveling compound until the mixture resembles a pourable milkshake.
Pour the self-leveling compound into the concrete cracks until they are full. Use a metal trowel to feather out the edges of the compound so they are even with the surrounding concrete surface. Repeat this process until all the cracks within the concrete are filled and leveled with the surrounding area. Allow the self-leveling compound to dry overnight.