Catholic Holy Water

All Christians can do this, especially priests:

Obtain pure water and pure salt.

"O Lord God Jehovah, Creator and Preserver of all things, in whose hand is the vital principle of every living being and the spirit of all flesh, hear we beseech Thee, the prayers of those who believe in Thee. Pour out Thy blessing on this salt and fill it with the benefits of Thy invisible power. In the name of Jesus Christ of Nazareth who is my Lord and savior, Amen."

"I exorcise thee in the name of God the Father almighty, and in the name of Jesus Christ of Nazareth His Son, our Lord, and in the power of the Holy Ghost, that you may be able to put to flight all the power of the enemy, and be able to root out and supplant that enemy and his apostate angels; through the power of our Lord Jesus Christ, who will come to judge the living and the dead and the world by fire."

"Heavenly Father, who for the salvation of the human race has built your greatest mysteries upon this substance, in your kindness pour down the power of your blessing into this element, prepared by many purifications. May this your creation be a vessel of divine grace to dispel demons and sicknesses, so that everything that it is sprinkled on in the homes and buildings of the faithful will be rid of all unclean and harmful things. Let no pestilent spirit, no corrupting atmosphere, remain in those places: may all the schemes of the hidden enemy be dispelled. Let whatever might trouble the safety and peace of those who live here be put to flight by this water, so that health, gotten by calling Your Holy Name, may be made secure against all attacks. Through Our Lord Jesus Christ, Thy Son, Who liveth and reigneth with Thee in the unity of the Holy Ghost, God, world without end. Amen."