Improving myself little by little

I'm just not made to speak in front of more than five people.
I always talk very fast and I actually did slow down considerably for the presentation, but I'm still not happy.
But then it went better than the last one I did where I started stuttering because I spoke too fast. And as long as it's only voluntary there's not harm in trying.
I should be happy that I've got no problems with understanding the facts, and I am. I just would be so much happier if I could actually manage to present them in a way that the others have a chance to understand them too.