An acceptance prayer might be...
My Lord and my God, in my acceptance of the type of death you plan for me, I join to your sufferings on the Cross. All that I ask is that you stand beside me and never leave me.
Lord, Father, I thank you for creating me.
Lord Jesus Christ, I thank you for saving me.
Lord, Holy Spirit, I thank you for purifying me.
Lord, one and undivided Trinity, I pray
That you will remember my faithfulness,
And so grant me a peaceful death,
At which suffering ceases for all eternity,
And I shall abide in your everlasting joy.
Most Sacred Heart of Jesus,
I accept from Your hands whatever kind of death
it may please You to send me this day (night)
with all its pains, penalties and sorrows;
in reparation for all of my sins,
for the souls in Purgatory,
for all those who will die today
and for Your greater glory.