Strong oral presentation skills are a key to success for engineers, scientists, and other professionals, yet many speakers are at a loss to tackle the task. Systematic as they otherwise can be in their work, they go at it intuitively, sometimes haphazardly, with much good will but seldom good results. Based on Dr. Doumont’s book “Trees, maps, and theorems” discussing effective communication strategies for rational minds, this lecture proposes a systematic way to prepare and deliver presentations. Among other topics, it covers structure, slides, and delivery, as well as stage fright.