A sacramental is a sacred sign that signifies effects obtained through the Church’s intercession. While all of the seven Sacraments are Christ-instituted and always do exactly what they signify ex opere operato (“from the deed done”), sacramentals are usually Church-instituted (though some are Christ-instituted). They work through the power and prayers of the Church. Sacramentals drive away evil spirit, and when piously used, remit venial sin and prepare the soul for grace.
Sacramentals can be material things (blessed objects, such as scapulars, Rosaries, Crucifxes, medals, Holy Water, etc.) or actions (the Sign of the Cross, genuflection, prayers, the washing of the feet on Holy Thursday, etc.). Note that only a priest has the power to bless an object and make it a sacramental.
Our crucifix, icons and other articles are examples of what we call sacramentals. According to the Catechism of the Catholic Church, sacramentals are sacred signs instituted by the Church to prepare us to receive the fruit of the sacraments and to sanctify different circumstances of our lives (no. 1677).
Exorcised oil is a special sort of sacramental. Besides the three oils which the church now reserves for use in the sacraments, the Church also recognizes the use of blessed oil for use by all Christians. The purpose of this oil is primarily for healing and protection from harm; but the oil can also be used to pray for all the blessings which the oil represents; that is, all the riches which are ours in Jesus. The oil can be used in praying for oneself or in praying for others. The simplest way of anointing is to make the sign of the cross on the forehead while saying the accompanying prayers. .If using on another, it is advisable to inform them that you are using blessed oil, which is not the sacred oils of the Church, and are not administering a sacrament of the church.
Exorcised salt works on a given place through sprinkling in rooms considered infected by the devilish forces’ actions, e.g. in places where evil spirits were summoned, pagan or spiritistic rituals took place. It is also used in the protection of houses, homes, farm buildings and fields, if a suspicion that they are under the influence of curses arises. Salt may be added to food if a suspicion of being enchanted through a meal arises.