Methods of protecting from evil spirits vary across religions and cultures. For example, Wicca and Catholicism both have different methods, ranging from prayer to the use of gemstones and herbs. Catholicism names holy water, blessed salts and staying away from things such as Ouija boards as methods of protection. Wicca traditions use gemstones, such as emeralds and bloodstones, along with meditation and speaking certain words to protect a person from evil spirits.
The primary defense against evil spirits in Catholicism comes from the Christian Bible, but there are also Catholicism-specific methods such as using an exorcist, attending mass, praying the rosary and wearing blessed medals from saints.
Wicca teaches using certain gemstones while meditating to create a circle of protection. Using incense such as Palo Santo, sandalwood or frankincense is another cleansing method, as well as salt. Wicca also teaches using communication with the spirits as a last resort. The communication is supposed to be polite and asks the spirits to kindly leave the area.
Ghost investigators such as the duo of Jacob Rice and Saleen Graham from Ghostly Activities list a variety of herbs on their site that they claim can keep away evil spirits. Some of the herbs listed include amaranth, angelica, blackberry, clove and garlic. Uses include wearing the herbs and hanging them about the house.