There are many different ways to clean a CD. There are free home remedies you can use and many retail products, too. Most importantly, do not use household products like Windex or 409. Do not wipe in circles and don’t use spray cleaners. Toothpaste is a tried and true method that works. Gently rub a layer of toothpaste over the disk and let it sit for 5 minutes. Using gentle pressure, wipe off the toothpaste while running water over it as you wipe. Another more common method is wiping the CD with a anti static cloth. Clean with an outward pattern. Not in circles.