1. He was terrified of breaking it, so I told him that there was nothing he could possibly do to it that I couldn't fix. I made sure to sound overly confident -- almost like I was challenging him to break it. That gave him the confidence to do whatever.
2. Every time there was a problem with it, I would Google the answer in front of him, and he'd watch me figure it out in real time. Eventually, he got the confidence to start Googling things himself. The tech support calls dropped off pretty steeply after that.