Procedure:
1- Masking tape to protect you edges and neighbor overlap columns.
2- Separating the rocks or sand from the wall bottom part.
3- Connecting the spryer machine to the outlet power.  
4- Protecting or strapping any bush close to the wall.
5- Filling our water buckets.
6- The Magic time. 

A wall of 70 foot to 100 foot will take us 3 to 4hrs to finish.
depending if any subjects like animals, or buildings included. 

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