Well, according to the Exorcist Priest for the Archdioceses of New York, whom I heard on EWTN a couple years ago, one way of discerning of a person was possessed by a demon, was to have the Holy Eucharist in the room. He said he would place the Eucharist in some obscure place without the person’s knowledge. When the person was invited into the room, they would refuse, because something was stopping them. Once they go them into the room, the person would be very uncomfortable, and sometimes they would defecate on themselves. The priest would also offer the person a glass of Holy Water, without the person’s knowledge that it was blessed water. The person would either refuse to water out of fear, or would drink it and immediately spit it out claiming it was burning their mouth.
The point is, demons do fear Holy physical objects.
So, wear a Scapular is my first suggestion. Second, have the picture of the Sacred Heart of Jesus in your home. Also, have a crucifix in every room. Also, have a picture of the Blessed Mother.
Have these objects blessed by a priest beforehand and if possible, have the house blessed.
Jim