Acting confidently can go a long way to teach us how to feel and be more confident. If you practice acting confident for at least part of your day every day, you will notice a difference in a month.
How does a confident person stand, sit, and walk? How do they look at a person? A confident person will look you directly in the eyes, wont they? How do they speak? They dont use a small voice, do they? A confident person is not afraid to ask for things, or to speak with strangers.
If you have somewhere to go like a job interview or on a date, take a few minutes before you go to daydream how a confident person would do it. Do you have a role model? Perhaps there is someone in the movies or life that you wish you were more like. How would they handle the situation? Have fun in the privacy of your home play-acting.
Sometimes you can rehearse situations with a friend to help you with your confidence. This is great for becoming comfortable with job interviews or dealing with customers. Practice and familiarity makes us feel confident.
If you would like to become good at job interviews, you could also apply for many jobs, even ones you dont want. At first you...