Get as much practice as possible. Book extra lessons with your driving instructor. In your final sessions, ask the instructor to concentrate on the manoeuvres you find most tricky.
Complete at least one 'mock test' in which your instructor ensures that conditions are as realistic as possible, providing a full debrief at the end of the session.
Don't listen to the advice of your friends / family. They doubtless mean well, but their instructions may be confusing, misguided or otherwise unhelpful. Remember that your driving instructor has years of experience as well as a professional training.
Ignore driving test horror stories. There are hundreds of them doing the rounds. A couple may even be true.