cultural considerations
because english is so widely used around the world, it is quite possible that many members of your audience will not be native english-speakers. in other words, they will not have an anglo-saxon culture. even within the anglo-saxon world, there are many differences in culture. if we hypothetically imagine a german working for an israeli company making a presentation in english to a japanese audience in korea, we can see that there are even more possibilities for cultural misunderstanding. you should try to learn about any particular cultural matters that may affect your audience. this is one reason why preparation for your presentation is so important. cultural differences can also be seen in body language, which we have just discussed. to a latin from southern france or italy, a presenter who uses his hands and arms when speaking may seem dynamic and friendly. to an englishman, the same presenter may seem unsure of his words and lacking in self-confidence.
voice quality
it is, of course, important that your audience be able to hear you clearly throughout your presentation. remember that if you turn away from your audience, for example towards the whiteboard, you need to speak a little more loudly. in general, you should try to vary your voice. your voice will then be more interesting for your audience. you can vary your voice in at least three ways:
speed: you can speak at normal speed, you can speak faster, you can speak more slowly - and you can stop completely! you can pause. this is a very good technique for gaining your audience's attention.