More than half the things we say are not spoken words. Actually, most of what we communicate comes from how we communicate it rather than what we communicate itself.
Having a proper body language is achieved through years of practice and applying it. Its is fundamental to develop the ability of being persuasive with what you do, to make others listen actively to you, to make them pay you attention. All that can be obtained without saying a single word, because if you ask for attention but you are boring your listeners, they will start using their mobile phones, talking to their neighbour or doing something else that is not listening to you.
Adopt a leading attitude, keep eye contact, be active whilst speaking, respect when others speak, make yourself noticed (but without overdoing it). Those are some tips that you must take into consideration when speaking, because how you say things is more important than the things you say.