It has been a tradition in the Catholic Church to bless chalk at the Masses for Epiphany then use the blessed chalk as part of blessing one’s home in the New Year.
Use the blessed chalk to write the following above a doorway in your home:
20+C+M+B+21
As you are writing, pray the following prayer:
Lord our God, bless this household. May we be blessed with health, goodness of heart, gentleness, and the keeping of your law. We give thanks to you, Father, Son, and Holy Spirit, now and forever. Amen.