Nothing suppresses your charisma as much as self-doubt.

People simply repeat to themselves over and over again that they cannot achieve something or that they simply are not worthy of it, and over time, such repetition leads to the formation of conviction - these words become unshakable. If you allow self-limiting thoughts to take over the mind, they will become toxic to it, and will not allow you to rationally talk about personal potential, goals, opportunities and abilities. Instead of saying, "I can't do this," stop and ask yourself, "How can I do this?" This will help to properly tune your thoughts and find a solution to the problem.