Currently there is a great demand for trained cyber security professionals with hands-on skills. The need for these professionals stems from our reliance on technology in many aspects of our daily lives and the smooth running of modern governments, education and health services. These professionals are desperately needed to defend cyberspace from threats such as hackers and malware who threaten to disrupt such services daily. This paper presents an insight into current approaches taken in the practical teaching of cyber security. We also give requirements and best practices for future training platforms based on a defined teaching process.