To clean plastic bags after use, first remove any debris or residue. Rinse them under cold water to remove loose dirt. For a deeper clean, you can wash them with warm soapy water. Use a mild detergent and gently scrub the bags with a soft brush. Avoid using harsh chemicals or hot water as they can damage the plastic. After washing, rinse thoroughly to remove soap and allow the bags to air dry completely. Store them in a cool, dry place away from direct sunlight to prevent degradation.