Be confident, but not boastful or arrogant. A humble confidence is what you should be striving for.
If you lack confidence right now, fake it. Act confident. Keep your head up, shoulders back, an easy smile on your face, and speak clearly and with a firmness to your voice. Look others in the eyes when you’re having a conversation with them.
If you appear meek, unsure, and as if you lack confidence, whoever you are speaking with will pick up on it. They will take over the conversation. And if you’re not careful, they will bend the conversation to fit their needs and leave out your own.