The most gifted individual on earth has to construct confidence in his gifts from the basis of faith and experience, like anybody else. The tools will differ from one person to the next, but the essential task is the same. And you can take it with you into old age. There is nothing more inspiring than an old person who maintains his good will, humor, and faith in himself, in others, in the future. Conversely, the root cause of old people's despair is a feeling of not being wanted, of nothing to contribute, no more to conquer and become.
Most people have more to work with than they realize.
One noted physicist calls this unused excellencies and finding and releasing this potential in ourselves is one of the major challenges of modern life. The great danger is not that we shall overreach our capacities but that we shall undervalue and under-employ them, thus blighting our great possibilities. The goal of life is not a problemless existence, which would be unbearably dull, but a way to handle problems creatively. Confidence is delight - delight in living, in being who you are, in what you do, in growing, in the endless and sometimes exasperating adventure of what it means to be human. So, too, the mother who delights in being a mother does not worry overmuch about whether she fits the rules.