The most helpful advice I’ve heard is not to aim for perfection. When you focus too much on structure and technique, the talk often feels stiff. What really connects with people is speaking about something you truly care about.
The first time I gave a talk, I memorized the entire script and completely blanked on stage. Later, I spoke from the heart instead and it worked much better. Instead of trying to impress the audience, it might be more important to ask yourself why this matters to you.