It is at the reading of the gospel that we cross our foreheads, lips and heart to ask God “May the Word be in my mind, on my lips, and in my heart.”
This particular prayer and triple signing takes place right before the reading of the Holy Gospel at Mass.
Tiki, I learned it a bit differently but it is all the same prayer. The way I was taught, as a convert, is:
“May the words of the Holy Gospel be in my mind, on my lips and in my heart.”