Remember to breathe, drink water, and take your time. I feel for you. It will be difficult at first but the more you do it, the easier it will be. I also suggest asking a friend or family member to practice with you. Both of you call into a meeting room and pretend they are your audience. Do this as many times as you need to. Also, be confident in the information you are presenting. The more confidence you have, the easier the flow of your speech will be. And most importantly, remember that everyone in your position is nervous, unfortunately those of us with a stutter are more obvious than others. Good luck! You've got this!