Toilet duck man u need to relax a little man, you're making ME nervous, and I'm not the one going for the interview. Although, as freezing may recall, just 4 months ago I was in your shoes and I was asking a load of questions too.

If you want to do some reading prep, I suggest "Airline Interviews", not sure who it's by, but I found it at my pilot store. It was full of nice little ways of remembering rule-of-thumb formulas for things like descent planning, vdp calculation etc.

The biggest thing to do as others have said is to be relaxed and confident, without being cocky. The HR interview is where you win or lose. In my interview there were people turned down who were FAR more qualified than some of us who were hired, and I can say for a fact that the HR interview was where they made their decision.

You need to have the sound technical knowledge too for sure, and know ur plane well, but at the end of the day, they have to like you!

All the best to you and all others interviewing or waiting for the call.