Catholics make the Sign of the Cross by touching forehead, chest, left shoulder and right shoulder while naming the Holy Trinity. It is a short creed: it professes the Trinity and the cross by which Christ saved us.
It is very old. Around 211 the North African writer Tertullian wrote that Christians “at every forward step and movement… trace upon the forehead the sign” of the cross (De Corona, ch. 3). At first it was a small cross traced with the thumb on the forehead, still done at Baptism and before the Gospel at Mass; the large cross over the body developed later. Eastern Christians touch the right shoulder before the left.
In the name of the Father, and of the Son, and of the Holy Ghost. Amen.
In nomine Patris, et Filii, et Spiritus Sancti. Amen.
Traditional English and Latin. Public domain. “Holy Spirit” is also used.
Prayer texts are traditional public-domain English forms, Douay-Rheims Scripture, Latin originals, or our own literal renderings where marked. Passages labelled Tradition or Legend are pious accounts that historians have not confirmed. Prayer and sacramentals are not a substitute for medical, legal or other professional help, and no prayer guarantees a particular outcome.