It has been a tradition in the Catholic Church to bless chalk at the Masses for Epiphany, and then use the blessed chalk as part of blessing one’s home in the New Year.
Use the blessed chalk to write:
above the doorways: 2019 for the year; C, M, B for the 3 Magi – Casper, Melchior, and Balthasar – and for Christus Mansionem Benedicat, Latin for “May Christ Bless this House.”
As you are writing, pray:
Lord God of heaven and earth, you revealed your only-begotten Son to every nation by the guidance of a star. Bless this house and all who dwell here. Fill us with the light of Christ, that our charity and good will towards others may reflect your love