The interviewer is generally expecting you so when you arrive, you greet everyone you meet. You immediately introduce yourself, you are told where to go.
Make contact by looking your interviewer in the eye and speaking clearly "hi, I'm emie joy. Glad to meet you. How are you today"... something along those lines.
Even if you are nervous, try to make eye contact and speak clearly. If it helps, you can tell the interviewer that you are nervous and if it is your first interview, etc.