Using these sunglasses is easy. Just put them on your face, and the non - slip nose pads will keep them in place. When you need to change the lenses, simply use the magnetic clip. It's quick and won't leave fingerprints. When you're out cycling or on the trails, these sunglasses will give you a great view and enhance the colors around you. As for maintenance, use a soft cloth to clean the lenses. Avoid using abrasive materials that could scratch the lenses. Store them in a protective case when not in use to prevent damage. Don't expose them to extreme temperatures or direct sunlight for long periods as this might affect the performance of the lenses and the frame.