I found this tradition in a Catholic bookstore around my first Epiphany (which was in 2008), and have kept it a tradition in my household ever since. Basically, you are taking time on this day to consecrate yourself and your household to God for the year, up to next Epiphany, when you do it again. You can find prayers for this house blessing in several places online, this one is the site that I used tonight to bless my house and to consecrate myself to the Lord.
Since I live alone, I said all the prayers myself, aloud. 🙂
I prayed the Magnificat from the Bible I received from the RCIA program, when I was joining the Catholic Church.
Then I sprinkled holy water in each of the rooms of my house. I don’t really have a good “sprinkling” technique, so I kind of splooshed gobs of water in each room from my holy water bottle. I’m sure God can work with that. 🙂
I didn’t have any incense with which to incense each room in the house. Instead, I took a candle I received at a memorial Mass for my godmother, lit it, and prayed for her intercession in each room in my house. I tried to tailor my prayers to the activities that normally occur in each room (E.g. pray for friends and relationships, that I consume media that feed rather than diminish my soul, etc. when I was in the living room). I asked her to take all these prayers to the throne of the Lord.
As the last part of the house blessing, I inscribed + 20 C + M + B 13+ above the entry doors to my home.