If you remember nothing else, remember this
Charismatic people make others feel good about themselves. So the more you think charisma is about impressing the room with your wit and anecdotes, the less likely you are to achieve this aim and the more likely you are to be perceived as a self-centered tool.
Our attention spans are short, so you need to make the right impression quickly
And you can do this by moving slowly. Don't rush as you enter the room. Take your time to find a spot to settle in and you'll appear totally in control.
The more nervous you are, the more effort you should put into helping others feel at ease
Approach the person who's standing alone and have a good opening question lined up; they'll be delighted that someone has made it easier for them, and others will notice their delight and want to speak to you, too.
"Introduce people as if they should already know each other," " says Sarah Cooper, author of 100 Tricks to Appear Smart in Meetings. "It'll make them feel like they've missed many great opportunities by not meeting sooner, and they will thank you."