The sprinkling of a small amount of Blessed Salt over each room and especially over the main doorways of the house.
You can also make the sign of the cross on every door with Blessed Oil.
That is what I did.
Simply take a packet of ordinary salt and a bottle of pure olive oil to your Priest and ask him to bless them. They are very powerful sacramentals.
Of course, as is pointed out below, you may sprinkle Holy Water over your home also. Whilst doing this you can remember the Holy Souls in Purgatory especially those who are waiting for one drop of Holy Water to be freed into the arms of Christ in Heaven forever.