When people tell me they are nervous about speaking, I say: good.
Nervousness is energy. It is your body preparing you for something important. Speakers who feel nothing often sound flat. The ones who feel a little nervous have fire available to them.
The problem is not the energy. It is that it has nowhere to go, so it leaks out as shaking hands, fast speech and fidgeting.
Give it a direction. Move with purpose instead of pacing. Gesture fully instead of twitching. Put the energy into your voice and your eye contact. Channelled, nervousness becomes presence.