First get you CD and smear the toothpaste on the scratched surface (NOT TOO MUCH, ONLY ENOUGH). Then rub it around a little with your finger in an up and down motion, NOT A CIRCULAR MOTION, IT WILL RUIN THE CODING. Lastly, rinse it off with warm water in an up and down motion.
And Voila! A usable CD!
Step 3: After the resurfacing ( An after picture for weissensteinburg)
This is a different CD, not the blue one. And I am in the process. But anyways, note how the CD isn't too scratched.