The organizational structure of the text primarily follows a sequential or step-by-step process format. This method outlines specific steps to start a fire without matches or a lighter, providing a clear sequence of actions to follow.
If we categorize this using the structures you mentioned, it doesn't quite fit into "compare and contrast" or "cause and effect" but rather is an instructional or procedural format. It details the methodology without comparing or contrasting different methods or discussing causes and effects related to fire-starting.