Using this dog wheelchair is easy. First, place your dog gently into the wheelchair and secure the built - in harness around your dog's body to ensure a snug fit. Make sure your dog gets used to the wheelchair slowly by starting with short walks in a familiar area. When using, always keep an eye on your dog to ensure its safety. As for maintenance, regularly check the wheels for any debris or signs of wear. Wipe down the frame with a damp cloth to keep it clean. If you notice any significant damage, it's best to stop using the wheelchair and seek professional help. And remember, since it's a used item, there might be some normal wear, but that shouldn't affect its functionality.