The gray-finished saya benefits from gentle, regular care. Wipe the exterior with a soft microfiber cloth after handling to remove fingerprint oils, which can leave marks over time. Avoid silicone-based polishes, as they may dull the matte gray tones. For the blade itself, apply a thin layer of choji oil with a flannel cloth every two to three weeks, or more frequently in humid climates. Store the ninjato horizontally on a display stand or inside a sword bag when not on show, keeping it away from direct sunlight to prevent uneven fading of the saya and cord wrapping.