Identify your insecurities and/or fears, accept them, move on.
The acceptance of fear (for example) isn't the identification & suppression of it, instead you must do exactly what you don't want to do, give into it, openly allow yourself to feel afraid, it is after all merely a natural aspect of the human condition, nothing to be ashamed of, and then once you've allowed it to run it's course it'll inexplicably pass of its own accord, apparently having no further use of you.
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Or perhaps there's like a "fear event horizon" that once you've crossed makes the further experience of fear meaningless, well either way I honestly dunno how it works, all I know is that it does.
As for insecurities, well lets say you’re ugly, honestly we’ve all got aspects of ourselves that we consider hideous and paradoxically we’re all surprised to find everyone else is just as insecure, if not more so. For example I’ve got big ears, and worse still they’re different sizes, but when I learnt to stop comparing myself to others and accepted myself as who and what I was, the insecurity seemed meaningless, after all I’m the perfect me, nobody else can be me better than I can be myself and likewise nor should I care if I don’t compare to them, my baseline is my body.
An apple judged by the standards of an orange will always fall short, as likewise will a orange judged by the standards of an apple.
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