The present invention relates to a method for interactively providing waypoints to a mobile robot for use in the marking of a geometric figure on a ground surface comprising the steps of: i) Selecting a control function accepting manual positioning of a mobile robot at two or more target locations on a ground surface; ii) Positioning the mobile robot in proximity to a first target location to be marked on a surface, and directing a position determining device of the mobile device to said first target location to be marked; iii) Instructing the mobile robot to store the first target location as a first waypoint; iv) Repeating steps ii)-iii) to obtain at least a second waypoint; v) Selecting a control function accepting manual selection of a geometric figure for being marked on said ground surface; vi) Instructing the mobile robot to compute the best fit for the selected geometric figure on the surface based on the two or more waypoints; vii) Instructing the mobile robot to compute waypoint coordinates of the g