Hi gogz87,
focus on learning the motivation papers for stage 1 & 2 so that you know them inside out. With regard to the interview, it is a structured interview so its not technical, but rather lots of questions about you and your personality, with no feedback at all after each answer you give. Try and think of good examples for each answer you give. ie. "are you motivated?", "yes im a really motivated person", then you need to give an example.
Good luck
