Signature to Asclepeion was the practice of incubatio, also known as ‘temple sleep.' This was a process by which patients would go to sleep in the temple with the expectation that they would be visited by Asclepius himself or one of his healing children in their dream. During this time, they would be told what it is that they needed to do in order to cure their ailment. At the very least, they would wake up having not been directly visited by a deity and instead report their dream to a priest. The priest would then interpret the dream and prescribe a cure, often a visit to the baths or a gymnasium.
Source: Asclepeion – Wikipedia