Steps to follow :
1. Clean the disc. Even if a CD isn’t actually scratched or scuffed, dust, oil, and other surface contaminants can prevent it from playing properly. Thus cleaning the disc should always be your first move. Run warm water over the damaged disc to remove dust. If there is stubborn dirt or grease on the disc, gently rub it with your finger while you are washing it, and use a gentle detergent or liquid soap (with the water) or rubbing alcohol (in place of water).
Anytime you rub or wipe a CD, you should do so by starting at or near the center of the disc and rubbing straight outward toward the edge to prevent further scratching. Shake the water off and let the disc air-dry (do not dry it with a towel or cloth, and don't sun-dry it either).
2. Apply a very thin coat of Vaseline, liquid car wax, neutral shoe polish or furniture wax to the CD’s playing surface. Wipe excess off using clean, soft, lint-free cloth in a radial (inside to outside) motion. If using wax, follow manufacturer’s instructions (some need to dry before you wipe them off, while others should be wiped off while still wet).
You could also refer the video demonstration