When I was a kid my grandmother always said "Saint Martin Called Expedite" as she was taught that was his full name.
I frequently use multiple Saints in one rootwork, but I pray to each one seperately with focus and intention, and I rewrite their prayer to mention the other Saints I am working with as well.
example off the top of my head:
Opening Prayer adapted from "The Morning Offering"
O Jesus, through the Immaculate Heart of Mary, I offer Thee my Prayers, works, joys and sufferings of this day and hour for all my intentions of Thy Sacred Heart, in union with the Holy Spirit, I thank you for standing before the Throne of the Father on my behalf, and I humbly beg you to call out the prayers of St. Anthony, St. Dymphna, and St. Jude this morning. It is with worship and adoration that I, with no right, do ask this favor Oh Lord, in the Name of the Father AND the Son AND the Holy Ghost. Amen.
Prayer to St. Michael the Archangel
ArchAngel Michael, who defends the innocent, stands by the righteous, and hunts the demons in this world, I come before you desperate and alone. I ask that you will stand beside Our Lord Jesus this morning and argue my case to the very Throne itself. I would ask only that my son, D , be given the strength and courage to fight his very personal demon of addiction today. And, on bended knee, I beg you to protect my son from himself today. In the name of the Father AND the Son AND the Holy Ghost. Amen.
Modified "Unfailing Prayer to St Anthony"
O holy St Anthony, gentlest of Saints, your love for God and Charity for his creatures, made you worthy, when on earth, to possess miraculous powers. Miracles waited on your word, which you were ever ready to speak for those in trouble or anxiety. Encouraged by this thought, I implore of you to stand beside St. Jude and St. Dymphna this morning and and pray for my son, D , that his mind be calm and his cravings be muted, that today he can walk with the Lord. And I ask you to whisper guidance to him as you once whispered to the Sweet Infant Jesus, that he might know which path to take to bring him closer to Jesus and stronger in Faith, that one day his addiction will only be a memory best forgotten. The answer to my prayer may require a miracle, even so, you are the Saint of Miracles, only whisper my petition before the throne and the gratitude of my heart will be forever yours. In the name of the Father AND the Son AND the Holy Ghost. Amen.
Modified "Prayer to Saint Dymphna"
Oh Pure and youthful Martyr, who knows the price of obsession and addiction, I stand before you and beg, with tears unshed for grief, I beg that you will pray beside St Anthony and St Jude this morning for my son, D. I am filled of fear for him and ask that you intercede on his behalf, that his demon may be cast off and his mind may be calm. Please fill him with hope, and grant him the relief and cure he so desires. I ask this through Jesus Christ our Lord who suffered in the garden, Amen.
Modified "Prayer to St Jude"
St Jude, Patron of those things despaired of; pray for me, that I may receive the succour of Heaven in my necessities, and please stand strong with St Anthony and St Dymphna this morning and pray for my son, D , that he may walk away from his past and become as a new man with the strength of Faith. I beg you to intercede this day, and I pray for your guidance in this most desperate matter, In the name of the Father AND the Son AND the Holy Ghost. Amen.