The author, Kyle Kelly-Yahner, built a custom conference line using Twilio for his family's holiday celebrations. He started by registering for a free Twilio account and purchasing a phone number, then set up a voice request URL to host his code. The author used TwiML verbs to build the conference line, including `Gather` to read a greeting, `Join` to connect callers to the conference room, and `HoldInPlace` to start the conference. To add a touch of personality, he incorporated custom wait music from Donna Summer's "Last Dance" MP3 into his TwiML code. With these steps, anyone can create their own unique conference line for special occasions or everyday use.