Is it better to sit, stand or even walk when communicating with people? Well, it all depends.
It depends on the context, the size of the audience, and the situation. If you are in a conference room with 30 other people there and the firsts two presenters have been seated, you very well may want to stand. It is just easier for 30 people to see you if you’re standing. It is easier for them to hear you and see your face. It is also easier for you to move, be more expressive, and more confident and authoritative. It shows the level of importance you’re putting on your words by standing.
If you are in a conference room and you’re talking to one prospective client or one colleague and they’ve been sitting talking to you, if you, all of a sudden, stand up, it may seem really weird, artificial, and contrived. So standing isn’t always better but it often is.
There is also an option of walking. Steve Jobs famously liked to have meetings walking. He found it more conducive and reflective and thought that it encouraged relaxed conversation. There’s something to do when you’re not looking at the person in the eye for the whole time.
There’s no one perfect way of sitting, standing or walking around for a presentation or a meeting or a conversation. You’ve got to look at the immediate context, what your goals are, and ultimately, what is going to make your audience most comfortable and most able to focus on what you’re saying.