The most important thing an Altar Server does is pray.
Please, pay attention to the Mass and know the Mass parts so that you can engage the Mass, join in the prayer of the Church, and set an example for the people.
Make me clean, O Lord, and cleanse my heart;
that being made white in the Blood of the Lamb
I may deserve an eternal reward.
Gird me, O Lord, with the cincture of purity,
and quench in my heart the fire of concupiscence,
that the virtue of continence and chastity may abide in me.
O Lord, the portion of my inheritance and my chalice,
You are He who will restore my inheritance.
Invest me, O Lord, as a new man, who was created by God
in justice and the holiness of truth.
Upon approaching the Cross after the Mass
[May it (the Mass) be for your benefit.]
Server(s): Pro omnibus et singulis.
[“For all and for each”, pronounced pro OM-nee-boos et SING-oo-lees.]
The servers will also implore a blessing saying,
Server(s): Jube Domine Benedicere.
[“May the Lord bless us”, pronounced you-bay DOE-me-nay ben-ay-DEE-cher-ay]
Priest: Benedictio Dei Omnipotentis + Patris, et Filiis, et Spiritus Sanctis Descendat super vos et maneat semper. Amen.
[May the blessing of Almighty God, the Father, and the Son, and the Holy Spirit Descend on you and remain with you always. Amen.]