What Prayer/words are associated with the solemn sign of the cross? With the normal sign of the cross you are supposed to say "In the name of the Father and the Son and the Holy Spirit/Ghost" as you trace the cross on your body.

The solemn sign of the cross is the triple cross which is made on the forehead, lips and chest. In Catholicism this happens before the priest reads the Gospel during every mass. As we make the solemn sign of the cross we say "Glory to you O lord" in the Novus Ordo (Ordinary Form) or "Gloria tibi Domine" in the Traditional Latin Mass (Extraordinary Form), but that is not the prayer which is strictly associated with the motion itself.

I'm wondering what words are supposed to be associated with the solemn sign of the cross, and if there are different words depending on your country?
For example I've heard that the priest is supposed to pray silently to himself "May Christ's words be on my mind, on my lips, and in my heart" as he makes the motion, and I've heard that the congregation is supposed to pray something like "I believe with my mind, confess with my mouth, and live out in my heart, the gospel".

However I can't confirm this because google is giving me nothing and my memory is fuzzy.
Growing up, I was taught that it was tradition to silently say while making the Threefold Sign of the Cross just before the gospel is read with these words: "May the words of the Gospel be on my mind, on my lips, and in my heart." 


  The origin of the sign of the cross on the forehead and the heart is Frankish or German, and it probably entered into the Roman liturgy sometime between the years 800 and 1000. The sign of the cross on the lips was added rather later, but it is not clear when it became standard practice.
  
  The words we are taught accompany the gesture (besides "Gloria tibi, Domine") are "May the words of the Gospel be on my mind, on my lips, and in my heart." The middle element, "on my lips," seems liturgically proper for the minister proclaiming the Gospel, but is it liturgically appropriate for the congregation? EWTN


Here is a little more on this practice:


  Concerning the making the sign of the cross at the proclamation of the Holy Gospel, after the deacon or priest says, “A reading from the Holy Gospel according to ….,” he and the faithful make the sign of the cross with the thumb on the forehead, lips, and breast over the heart.  (The deacon or priest also makes the sign of the cross on the Lectionary or Book of the Gospels.)  The first recorded instance of making the sign of the cross at the proclamation of the gospel is found in the ninth century:  Regimius of Auxerre (d. c. 908) in his Expositio recorded how the people in the congregation would sign their foreheads, and the deacon would sign his forehead and breast.  By the eleventh century, as attested to by Pope Innocent III, the deacon would make the sign of the cross on the Lectionary or Book of Gospels, and then both he and the congregation would sign the forehead, lips, and breast.  The significance of the threefold signing is that we want to hear the Holy Gospel with an open mind, proclaim it with our lips, and cherish and safeguard it in our hearts.  We are imploring the Lord for the grace to receive, acknowledge, and then profess the faith that has been received in the Holy Gospel through our Lord, Jesus Christ, the Word of God incarnate. - What is the origin of the sign of the cross at the gospel, bowing at the Creed, and shaking hands for the sign of peace?