practice in the mirror A LOT. this will help you gain confidence if you see what you're doing for yourself. or video tape yourself and try and correct yourself when you actually do it.
calm your self down. the adrenaline is probably getting to you. you may think that this is a big deal, but do you really pay attention to any one else's speeches? i don't mean to be rude, but i don't think anyone will really pay attention to you. it works for me, thinking that.
if you mispronounce words and stutter, no one will think you're stupid. they'll think you're human. don't make a big deal out of it. people will only notice if you do.
it's not about the emotion in your voice. it's about the facts. especially in this class.
maybe write down a few notes in your notebook about keeping a steady pace and not to say "um" or "ah" in your speech. or not to twitch or such. it's what i do when i have a speech and it helps me calm down, so i don't have to remember the speech and my presentation.
before you present, take deep breaths and get yourself together. when you are looking around the class, look at everyone, not just one person or the wall. look at they're forehead. it's less intimidating but gets the listener involved. make arm gestures to get the listener's eyes up on you, instead of their shoes. don't fidget, or shift feet, unless you're allowed to walk around the room. it's distracting to your speech. don't be too quiet or to loud. stand tall. your feet sould be shoulder length apart and your arms at your sides unless you're making gestures or holding notecards.
calming down is the most important. don't make a big deal out of it or you'll over think it. relax. practice, and be confident. perhaps infront or a friend so they can critique you.
i know from experience that the apprehensiveness sucks the most. i hate waiting for my speech. when he's about to call out a name, i get so worked up i start to bite my nails or something. if you look confident, you'll sound confident.
good luck!!!