R.C. Sproul used to memorize his messages, but now immerses himself in the material as preparation, and then speaks without notes. He believes that this is important to preserve eye contact. A pastor who spoke from a full manuscript once asked Sproul to critique his message. Have a student calculate how many times you break eye contact with them during your message. Ask if it's distracting.
Some pastors write a full manuscript, but go to the pulpit with only an outline and notes .
This is essentially the student's outline that I give you. Try simply speaking from the student outline, and attach note cards or cutouts of any illustrations that are too difficult for you to digest. Other top communicators step to the pulpit with the full manuscript , but seldom look at it. I often speak from the full manuscript, but highlight key words, divisions or phrases in yellow, so that I can find my place at a glance. As I teach, I trust the Holy Spirit to prompt me as to what to leave out, what to add, what to especially emphasize.