I freeze in interviews, tips? - any advice?

I have an interview on Tuesday and my stomach is in knots. I have read a lot of threads here and could not find my exact situation. I want to come across as confident and honest. Any questions to ask at the end?

Thanks for writing this out. I went through something close to it last year, and it got easier once I kept a simple log of every call and form.

Prepare three stories with a clear beginning, action and result, and adapt them to the questions.