The Practicing Catholic was generous enough to share the Traditional Consecration Prayer to St. Michael the Archangel.
You can find it in print form HERE, or click HERE to read their article.
God Bless †
Traditional Consecration Prayer to St. Michael the Archangel
Oh most noble Prince of the Angelic Hierarchies, valorous warrior of Almighty God and zealous lover of His glory, terror of the rebellious angels, and love and delight of all the just angels, my beloved Archangel Saint Michael, desiring to be numbered among your devoted servants, I, today offer and consecrate myself to you, and place myself, my family, and all I possess under your most powerful protection.
I entreat you not to look at how little, I, as your servant have to offer, being only a wretched sinner, but to gaze, rather, with favorable eye at the heartfelt affection with which this offering is made, and remember that if from this day onward I am under your patronage, you must during all my life assist me, and procure for me the pardon of my many grievous offenses, and sins, the grace to love with all my heart my God, my dear Savior Jesus, and my Sweet Mother Mary, and to obtain for me all the help necessary to arrive to my crown of glory.
Defend me always from my spiritual enemies, particularly in the last moments of my life.
Come then, oh Glorious Prince, and succor me in my last struggle, and with your powerful weapon cast far from me into the infernal abysses that prevaricator and proud angel that one day you prostrated in the celestial battle.