We've even made it easy to enroll. In fact, you don't really have to do anything. When you purchase the AppleCare Protection Plan with a new Mac, you'll be automatically registered in the plan. Shortly after your new Mac ships, we will mail you an AppleCare Welcome Packet, which includes your Proof of Coverage, as well as a Getting Started Guide with plan terms and conditions.
It's a good idea to keep this packet with your other Apple-related documentation for easy reference.