Although this is dramatized, this clip from Drake and Josh perfectly depicts exactly what NOT to do in any given speech or delivery.
First of all, Josh begins thinking about the possibility of making a mistake, which is exactly when he starts tripping himself up! In order to succeed, one must clear their head, relax, and give their presentation without worries of mistakes. Everyone will mess up, so don’t let it get in your head.
Second, Josh’s delivery does not sound natural. His words come off as unnatural, and he begins to stutter and trip over his sentences quickly into the news cast. In order to avoid this, make sure your speech is well-rehearsed and about a topic that you feel comfortably knowledgeable about; that way if you do make a mistake, you have the knowledge to correct yourself.
Third, Josh’s body movements seem unnatural. While it’s obviously dramatized, Josh begins to twitch, tighten up, and give uncomfortable face expressions (not to mention sweat a lot). To boil it down to our speeches, don’t be stiff! Make yourself look comfortable in the environment and you will in turn feel comfortable as well. In order to do this, maybe visit the OBS a few times to get an idea of what presenting there will be like.