What did Brian use to clean his shelter?

In chapter 11, Brian cleaned his shelter by smoothing out the sand and hanging up his windbreaker. He might have used his hands or sticks to level the disturbed sand. Either way, there was not much Brian could do to clean up his shelter. The actions associated with cleaning up the shelter were a comforting ritual for Brian, nothing more.
The text tells us that Brian's shelter was a hollow carved out of a rocky ridge. To make the shelter a safer place, Brian wove a wall of dead branches across the opening of the rock. He left an uncovered opening of about three feet. Accordingly, the inside of the shelter was about fifteen feet long and eight to ten feet deep.
To keep himself warm, Brian used dead branches to make small fires in his shelter. The fire kept the mosquitoes out of his shelter, which made Brian happy.