In the majority of Art A-Levels and GCSE's what the examiners are looking for is a steady and concise development of process within your project.
What you need to ensure is that you give them a wide range of media and materials used while also showing a willingness to explore and expand your project. This was one of the most difficult aspects people in my year were trying to grasp as well as for me, but having managed to achieve an A*, I know how to present the work and give direction to achieving a high standard grade.