Self-acceptance boils down to not holding yourself to unreasonable standards. The fact is that we’re all messes in our own way. None of us, though, look quite as messy as we actually are, because we tend to conceal the untidy bits from public view. It’s easy to get the idea that most people have their act together better than you. You imagine some ideal self that you ought to be, and the way you really are looks pretty crappy by comparison. Because of this, you feel that the current version of you is unworthy of love. Only when the “real you” upgrades to meet the standard of the “ideal you” will you be worthy of love.
Self-acceptance starts with a more realistic understanding of what human beings are actually like behind their public personas. Then you can begin to see through the myth of your “ideal self”. That doesn’t preclude working on your habitual behaviors that make things harder on yourself and others, but it does help you see that you’re probably just as worthy of love as most folks, even without an upgrade.