I always want to give you the inside scoop and tiny nuances that help make an overall great presentation. Sometimes what I tell you has nothing to do with your speech. This is one of those times.
Make sure you have some breath mints with you on stage or in your pocket. I've gone up to congratulate people on a great speech and about fell over because of their bad breath.
You would think all that wind you are blowing on stage would disperse bad breath, but for some reason after speaking for an hour or so, every foul smelling odor from your stomach wants to leap forth to your audience. It may be because you just had lunch with the group and didn't have time to brush your teeth, or it could be just because of the constant rush of air from your belly.
This doesn't matter too much if you are far from them, but if you bring them up on stage with you, or if someone wants to talk to you afterward, it can really reflect poorly on you. I'm sorry to have to tell you this one, but one big shot speaker I saw had nose hairs sticking out so far you could braid them. He had the nerve to hit on the women in the audience as they came up to talk to him. I can only imagine what they were thinking about this big jerk.
So, watch the hygiene. You don't want to negate a great speech with poor personal habits.