There are things you should do to improve your presentation. Among them:
- Know your material
- Video yourself rehearsing (and watch it!)
- Rehearse some more
If you approach public speaking thinking that there's a perfect or flawless way to deliver your presentation you're going to be sorely disappointed. The goal of your speech should be to convey information well not to be an idealized silver-tongued version of yourself. Simply BE yourself.
I doubt there's a realistic person out there, even among professional speakers, who is ever 100% satisfied with their delivery. also adds a level of stress to your preparation and does nothing to settle nerves.