Yeaa.. Presentations fucking blow, but your appearance dictates how your class will perceive you. Be confident, dress to a T, and smile. Don't think about what will happen when you stutter, try and concentrate on the knowledge you are trying to give to your classmates. Practice the tricky words, look up a thesaurus (I have trouble with words with multiple alveolar consonants in rapid succession; better, stutter, benevolent etc). I've been stuttering since day 1 as well brother, I've taught myself that concentration and confidence are some of the best ways to overcome it. Meditate on it, and practice in front of people who you love, and most importantly, don't give in to the nervousness.