Interview nerves, what actually helps? - what worked for you?

I have an interview on Monday and my stomach is in knots. I have practised answers but they sound stiff. How do you prepare answers?

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

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