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Once all pavers are in place and the perimeter mortar has set, spread polymeric sand over the entire paved surface. Use a push broom to sweep the sand into all the joints between the pavers, ensuring they are completely filled. Remove any excess polymeric sand from the paver surfaces. Finally, thoroughly wet the patio with a fine mist from a water hose. This activates the polymers in the sand, causing it to harden and lock the pavers in place. Allow the patio to dry completely.