The candles are lit during the Sunday services, starting with the first Sunday. Purple for the first two weeks, and typically pink for the third, then purple for the fourth (and last) week.
This lectionary page provides the readings: http://lectionarypage.net.
As for meditations, I'll be reading Love Came Down: Anglican Readings for Advent and Christmas by Christopher L. Webber: https://www.amazon.com/Love-Came-Down-Anglican-Christmas/dp/0819218987.