Practice, practice, practice, practice. Whenever I need to do a presentation or a speech, I literally practice it until I know it by heart, then I do it some more. At least in my experience, by knowing exactly what you're going to say helps with the nerves. Part of the reason why I hate PowerPoints so much. You need to go off the cuff more. Edit: regarding the ticks, I had the same problem overcoming it in speech therapy. I would kinda, "keep time" with my finger or my leg or my head. Kinda like keeping a beat. It got to the point where i couldn't overcome it, so someone sitting across from me kept her feet on top of mine, someone else held down my hands, and when I began nodding my head, my therapist held my head in place while i spoke. A bit extreme, but it helped me get over my ticks. Not sure if yours are the same type of thing though.