Review of studies published in medical education journals over the last decade reveals that teaching medical professionalism is essential, yet challenging. According to a recent Best Evidence in Medical Education (BEME) guide, there is no consensus on a theoretical or practical model to integrate the teaching of professionalism into medical education. The aim of this article is to outline a practical manual for teaching professionalism at all levels of medical education. Drawing from research literature and author's experience, Twelve Tips are listed and organised in four clusters with relevance to (1) the context, (2) the teachers, (3) the curriculum, and (4) the networking. With a better understanding of the guiding educational principles for teaching medical professionalism, medical educators will be able to teach one of the most challenging constructs in medical education.