Charisma is all about how you act, not what you have to say. You can be more charismatic in a conversation by always waiting two seconds before you respond to something.
Photo by Jonathan Tommy
Good conversation echoes the back and forth of a tennis match, and requires active listening and avoiding being rude at all costs. Despite how interesting you think your comment is, interrupting someone else's comments to get it out in the open will only decrease your likability. To help yourself avoid interruptions and boost your charisma, Stephen Andrews at Dumb Little Man suggests you follow the "two-second rule":
...try to count out two seconds in your head before you reply to what people say. You will first notice that, often, people were not finished speaking. They merely paused. By waiting two seconds, you allow them to finish their entire thought. Rather than interrupting the other person, you communicate genuine interest and attention to what they are saying. Second, waiting two seconds creates a moment of tension between the end of their thought and your reply. Because most people immediately jump into their reply, in waiting two seconds you communicate confidence and power.
People like to know that they're are actually being heard, and a short pause shows them that you listened and thought about it before you did anything else. Remember, charisma and likability aren't based on how smart or talkative you are, they're about the way you carry yourself and conduct communication with others. Make other people feel valuable and you become valuable.
Three Easy Ways to Drastically Improve Your Charisma [Dumb Little Man]