-- public speaking (and confidence FAIL)

So I'm recovering from co-teaching a class today. I'm way too shy to stand in front of group comfortably so while it's rewarding (when over), it's enormously emotionally draining. Here's what I wrote last time I had the class, basically was the same scenario this time.

I remember looking down at my outstretched hand, noticing the pen it held was quivering, and thought "huh, that sucks. I need to calm down." Any public speaking tips would be appreciated, or even any tips on how not to be a spaz when nervous, maybe I can use them at the dentist's!

image from CartoonStock's public speaking collection.