If you’re looking for something to say to the Lord before you go to sleep, you may want to try this prayer by Saint Alphonsus Liguori. It’s one of the nicest that I’ve seen.
A Night Prayer by Saint Alphonsus Liguori
Jesus Christ, my God, I adore Thee and I thank Thee for all the graces Thou hast bestowed on me this day. I offer Thee my sleep and every moment of this night, and I beseech Thee to keep me free from sin. Therefore I place myself in Thy most sacred side and under the protecting mantle of our Lady, my mother. May Thy holy angels help me and keep me in peace, and may Thy blessing be upon me. Amen.