[Therion] Surveying Maze Caves

Hello all, I have a question regarding surveying (and mapping) extremely mazy multi-level caves. There is a cave near my home that has never been mapped, I assume due to it's extremely mazy nature. I am considering taking it on as a project, however, I have no idea how to survey it. Do any of you have advice as to how to best manage such a survey? I imagine I will have to be extremely careful with how I create scraps in therion, as well. I can think of several places in the cave that have 5 or 6 passages all meeting in one small room. Any advice would be greatly appreciated. Thanks :-). Sincerely, Jonny Prouty