<human>:  How do I fix a cracked patio slab?
<bot>: The first step in fixing a cracked patio slab is to identify the cause of the crack. Determine if the crack was caused by settling of the ground, a heavy load, or some other factor. Once the cause has been identified, inspect the slab to make sure there is no structural damage. If the slab is still stable, you can repair the crack with a concrete patch. Apply the patch with a trowel and smooth it out to create a level surface. Allow the patch to dry completely before returning the patio slab to use.