Shame and self-doubt can arise from many sources, including unhealthy societal messages, trauma, negative thought patterns, or even an existential malaise. Sometimes just taking good care of the basic human organism can facilitate self-confidence. Eating better and getting enough sleep can markedly improve our mood and thought processes. As powerful as exercise is biologically, I think it’s even better psychologically. Often we can discover our true selves through the arts.
Similarly, recent exciting research suggests that we may be able to increase our self-confidence by training our brains. Scientists have identified brain activity patterns that can predict the confidence level of an individual. Additional research has shown that we can hone our neural activity to internally enhance our self-confidence. You can read more here.