When you face a challenge ,"fake it until you can make it." This means that you should act as though everything were working out well, even when you have doubts. Put a smile on your face,even if it isn'treal, and eventually it will be a real smile.

Stand up straight with your head high and walk with purpose .

You will start to actually feel more confident. If you are acting like a successful person ,it may feel strange at first. But the more you practice your role as a successful person,the more comfortable you will be. Soon, when you reach your goals and you are truly successful,you will have practiced the role, and you will be the person you have been playing.