How would you get out?

Put yourself in one of the episodes, how would you get out? In the episode where the 4 men in the Amazon, Yossi was missing for a longer time than anyone. If I were in his position I think I would just try and make some sort of rope or twine, something to pull across the river as a kind of trip wire so anyone going by it would literally feel it and it would be like a bread crumb I suppose.