What should we do? Everyone thought John the Baptist was the saviour, but he wasn't. He said that while he was a prophet, he was nothing more than a messenger for the Messiah who was to come. So what should we do. John tells us to repent, and to make room for the Messiah. Repent means to ask God for forgiveness for our sins, which comes to us through the sacrament of reconciliation. Father Matthew calls on people to go to confession before Christmas.
Decorations in the home can help us to stir up preparation for Christmas, but we are to "make a straight path" for Jesus from our head to our heart. Starting a relationship begins with the head and leads to our heart. Knowing Jesus is totally different from loving Him. Reading the Gospel daily is one way to to help make straight the path from our head to our heart.
So the answer to the question, what should we do, is to make room in our heart for Jesus. Jesus is the reason for Christmas, and we should share this understanding with others by inviting someone to Mass. Repent and prepare a way for the Lord, our Saviour, Jesus Christ!