Sweep or vacuum loose debris from the cement
Wet the painted area with water
Apply a graffiti remover or paint stripper made for masonry
Let it sit for the recommended time
Scrub with a stiff-bristle brush
Rinse with clean water
Repeat if needed
Use a pressure washer if the cement can handle it
For stubborn spots, apply acetone or mineral spirits to a small test area first
Scrub again and rinse thoroughly
Use a poultice remover for deep stains
Seal the cement after cleaning if desired