Natural self-doubt is a part of being human. We are self-correcting, growing creatures, who learn from our mistakes thereby giving those mistakes great value and meaning. We must use natural self-doubt as a tool and not be crippled by it.
But there is also unnatural self-doubt. That appears when we are afraid of repeating the experience of letting someone else down, while trying to do what is right for us.
It's hard enough to live up to our own expectations. Trying to live up to other people's is impossible and a waste of time. I cannot stress strongly enough that—until we stop allowing ourselves to be paralyzed by worry over what others might feel about us and our actions—we are never going to get anywhere.
You can literally profit from your mistakes, and learning from them is the only way to transform them into positive influences on your life. Remember, even the unlikely perfectionist who finally attains perfection is never free of natural self-doubt. It is an important part of being the best we are capable of.
On the other hand, if you realize that you are plagued by unnatural self-doubt, the only real remedy is to remember Shakespeare's memorable line: "To thine own self be true." You must forgive yourself for forgetting whose approval you really need (your own!) and go about your business secure in the knowledge that you will do the right thing. Learning to trust yourself is an important part of spiritual growth.
Here’s a tip to help you curb your self-doubt: Re-program your conscious and unconscious flow of thoughts and images by wearing a rubber band around your wrist. Every time you notice yourself allowing unnatural self-doubt—or any other kind of habitual negative thoughts—to clutter your mind, snap It! This little zap will bring you back into the present and works as a signal to you and your unconscious mind to replace your negative thoughts with healthy, positive ones. This is a simple way to recondition yourself to think more positively.