Sure thing. Drop a small flag that’s a color the enemy never expects, only visible from a hidden perch. Or use a simple radio chain: your outpost talks to a satellite via a small beacon, but the beacon only transmits when you’re on the move, so no static signature. If you need to stay truly silent, leave a carved stone with a tiny, coded inscription and set up a pre‑arranged meet spot – just the right amount of dirt and a notch will do. Always keep a backup: a folded piece of paper in a hollowed log, marked with a sigil you only use in emergencies. Nothing loud, nothing obvious. Keeps your spot a mystery.