The Z-Wave range extender and the sensors in the kit are pre-paired with the base station, so you just need to enroll them into the app. Ring also sent me a couple of add-on door/window sensors so I could experience the full onboarding process. This simply involves scanning a QR code on the device, verifying that the PIN printed below the QR code matches what’s displayed in the app, and then pulling the battery tab.
Update 1/24/16 - I have found a fantastic use for the Ring Doorbell and Chime. My mother-in-law, now in her 90s, lives by herself. She has become hard-of-hearing and often does not hear the doorbell. By installing the Ring on her door, she now is bothered much less (solicitors tend to recognize it and don't seem to like it) and when someone rings the bell, the Chime, placed by her favorite chair, gives her a better chance of hearing someone at the door.