Cleaning a kneaded eraser involves two main steps. First, you can stretch and knead the eraser to help lift away any dirt or graphite that has accumulated on its surface. This process is effective because the eraser's pliable nature allows it to absorb and trap particles. If the eraser remains dirty after this initial cleaning, you can wash it with mild soap and water. It's important to rinse it thoroughly to remove any soap residue and then allow it to air dry completely before using it again. This ensures that the eraser maintains its effectiveness and does not transfer any dirt back onto your paper.