I know it's easy for me to say this, but you need to relax and have a cool, calm attitude to your driving. You need to show competence and ability to look ahead, and show forward planning in your driving. Also, at this stage in your driving campaign you need to show the Examiner that your are safe to be on the road.
Just imagine you've got 'Granny' in the back seat with a boling hot cup of coffee, and boy will she shout if you don't give her a nice smooth drive.
Best of Luck, let us know how it goes!