This paper describes a systematic process for the development of educational audio-visual materials that are designed to prepare patients for potentially threatening procedures. Literature relating to the preparation of patients for potentially threatening medical procedures, psychological theory, theory of diffusion of innovations and patient information was examined. Four key principles were identified as being important: (1) stakeholder consultation, (2) provision of information to prepare patients for the medical procedure, (3) evidence-based content, and (4) promotion of patient confidence. These principles are described along with an example of the development of an audio-visual resource to prepare patients for chemotherapy treatment. Using this example, practical strategies for the application of each of the principles are described. The principles and strategies described may provide a practical, evidence-based guide to the development of other types of patient audio-visual materials.