Remember to take it slow when you are moving around campers, and also to stay out of their direct line of sight. When a camper starts to get suspicious, the meter above their head fills with a white bar. After that, it will fill with an orange bar, and if this fills all the way the camper will be alerted to your presence.
Should this happen, any rangers in the current area will be immediately alerted to your location and will hunt you down. Quickly duck into a berry bush and stay completely still to hide. You should lose most rangers this way, but you can also duck into an outhouse or a tent if there is one nearby.
You may also come across dried bushes – they look a little gray compared to regular bushes. If you walk up to these and hide in them, you can actually move around with it on you as the bushes are light. Staying still hides you in the bush, so these are useful for getting around populated areas.
You should buy the clothes from Raccoon’s shop as soon as you can afford it, as they will allow you to wander around the campers without alerting them. Rangers can see right through your disguise though, so be careful!