Sign of the Cross, and any phrase that is used in exorcism: Jesus, Mary and Joseph; Blessed be the Precious Blood of Jesus Christ.(demons hate hearing Precious Blood) Mary's name.
I had an encounter with a man in Texas 10 years ago. He knew of me (catholic) and stranger to me (someone's guest). He spoke of a minister, women who had healings take place. After he spoke and before I asked the Holy ghost for help.
I remembered the demons hatred for the Precious Blood. So, I asked this man, "Where do you suppose she gets her powers?) He responded, "The Holy Ghost". Oh, I said, "What about the Precious Blood of Christ". He stood up, and in raged screamed, "What of it!". I left the room. About 20 min. later he apologized.
In my opinion, he harbored a demon who did not like what it heard. He could not control his rage. He had to excuse himself like one does after a burp they can not control. Wow, it is a sight to see!