Step1: Clean-Remove all the oil, pitting, paint and weathering from the paving stone. 1. To remove grease, besmear sodium. Have it soaked for 2-3 minutes and then repeat renovation with small brush. Don't let it dry out but thoroughly flush. It can be cleaned with repeat cleaning if necessary. Note: the oil penetrated into paving stones will float on the surface in 24 hours after cleaning, and if so, clean again. Gray paving stone will leave black marks after removing grease.It can be cleaned with remover or weathering remover to make the marks pale. 2. Pitting can be cleaned by remover. Removing the traces of paint, tar and rubber needs to use the correct remover. To bresmear the right remover on the surface of paving stone the stains, and brush it with small brush after disappearing, immediately flush it with water. Repeat flushing if necessary. Step 2: Surface Preparation No matter the surface of the paving stone is new or old, or it has been maintained before, it also needs to be cleaned again. Using the weathering remover to dissolve the weathering on the surface to make sure the cleaning can be unit.