"A good lecturer is thus talking with and not at or even to his or her listeners. To manage this, the lecturer needs to be closely attending to the audience's every move, gesture and sound. Perversely, this cannot be done by watching the audience, as such. A good lecturer speaks directly to and watches the response of single, identifiable people,* instead of doing something clichéd, such as "presenting a talk" to an audience. Everything about that phrase is wrong. You don't present. You talk. There is no such thing as "a talk," unless it's canned, and it shouldn't be. There is also no "audience". There are individuals, who need to be included in the conversation. A well-practiced and competent public speaker addresses a single, identifiable person, watches that individual nod, shake his head, frown, or look confused, and responds appropriately and directly to those gestures and expressions. Then, after a few phrases, rounding out some idea, he switches to another audience member, and does the same thing. In this manner, he infers and reacts to the attitude of the entire group (insofar as such a thing exists).
* The strategy of speaking to individuals is not only vital to the delivery of any message, it's a useful antidote to the fear of public speaking. No one wants to be stared at by hundreds of unfriendly, judgemental eyes. However, almost everybody can talk to just one attentive person. So, if you have to deliver a speech (another terrible phrase) then do that. Talk to the individuals in the audience - and don't hide: not behind the podium, not with downcast eyes, not by speaking too quietly or mumbling, not by apologizing for your lack of brilliance or preparedness, not behind ideas that are not yours, and not behind clichés."
Jordan B. Peterson - 12 Rules for Life: An Antidote to Chaos, 2018