Spray a rag with all-purpose cleaner. Lightly moisten the rag rather than drenching it.
Rub the marked stair risers with the cleaner-moistened rag using gentle, circular motions. Remove as many markings as possible.
Dampen another rag with water. Lightly wipe the stair risers to rinse off the all-purpose cleaner.
Wipe the wet stair risers with a towel. Dry the risers thoroughly, even if marks remain.
Inspect the white stair risers for stubborn black marks. If any marks or traces of scuffs remain, moisten a melamine foam cleaning eraser with water. Thoroughly wring out the eraser.
Rub the moist foam eraser over the remaining scuff marks. Using circular motions, gently scrub the marks until they come off.
Wipe the wet stair risers with another towel. Dry the stair risers thoroughly to avoid slipping hazards.