Being able to interact and communicate with robots in the same way we interact with people has long been a goal of AI and robotics researchers. In this paper, we propose a novel approach to communicating a navigation task to a robot, which allows the user to sketch an approximate map on a PDA and then sketch the desired robot trajectory relative to the map. State information is extracted from the drawing in the form of relative, robot-centered spatial descriptions, which are used for task representation and as a navigation language between the human user and the robot. Examples are included of two hand-drawn maps and the linguistic spatial descriptions generated from the maps.