I freeze in interviews, tips? after 15 years as a dental hygienist

I have an interview on Thursday 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. 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 2 months ago, and it settled down once I kept a simple log of every call and form.