Cleaning the deck or immediate surrounding is important as dirt or debris can find their way into your pool sooner or later. To avoid that from happening, it is best to sweep or hose down the debris near the pool to remove it.
Cleaning the pool wall
As for the cover, if it is a floating type without a roller system, make sure that the cover is placed on a clean surface, otherwise the dirt it has gathered will end up in the pool. For a mechanized cover system, simply hosing the top of the cover with water will remove any dirt as you roll it up.
