Relax...
...okay that wasn't very helpful... Sorry
If you've done a mock test then you are in a good place. My flight test was almost a carbon copy.
Remember, the examiner is looking for an excuse to pass you, they aren't trying to trick you.
Treat the examiner as your first passenger. Explain what you are doing. They aren't mind readers. Let them in on your train of thought.
They are not looking for perfection. Making a mistake is not the end of the world. They are looking for how you deal with them
If you are unsure of what they are expecting from you then ask.
Confidence helps. Once I was back in the circuit on my home turf.... I actually kinda enjoyed it !
Best of luck...