How do you go about instructing and communicating appreciation for the colors of the church year and the seasons they support?
Some liturgical creativity is in order for this task. Think of the rainbow. It is a vivid reminder of God's promise given to Noah and his descendants. Traditionally, five basic colors of a festive, penitential, and neutral nature have been used in most liturgical congregations. In recent times, with liturgical renewal, three additional colors (blue, scarlet, and gold) have been added to the basic five of white, red, green, violet and black. 
Blue, is the more contemporary color increasingly used by many congregations in their observance of a new church year. Advent, a preparatory time of waiting and watching, communicates the message of hope. Blue, the color of the sky, helps convey that powerful message. Our Christian faith rests on the hope that Christ, who came in history assuming our flesh, will also return on the last day of time from that same blue sky He ascended long ago.