Survivalist Bear Grylls says that one of the main reasons people die in the wild is they get their priorities wrong. “The human reaction is panic. When you’re in a very new and scary situation—the plane’s crashed or your car’s broken down or you got lost—the first reaction is you’re gonna surge with adrenaline, your heart starts going. When that happens, you start making mistakes and you can make bad situations worse.”

Bear says you need to make sure your priorities are in the right order. He remembers using this simple sentence: Please Remember What First (or PRWF)—Protection, Rescue, Water, Food. He adds, “And think calmly when you’re in that situation.”

Protection: “The first thing is to make yourself safe. Protect yourself from imminent danger, from the terrain, from the weather.”

Rescue: “Second priority is rescue. It means setting yourself up for rescue. Make yourself visible. There’s no good being safe in a cave somewhere and it’s snowing and it covers over and you could be there for months and nobody’s ever going to find you. Set yourself up to be spotted.

“There are different ways to help rescue teams spot you, Bear says. “Build a fire or use markers that are reflective and highly visible from the air. Anything that is contrary to nature. You very rarely get straight lines in nature, so anything straight— big squares, whether you’ve made it with rocks or logs or blankets—something that’s gonna catch a search-and-rescue pilot’s eye.”

Water: “Third priority is to find water. Water is absolutely critical.”

Food: “Fourth priority is to find food. How long can you survive without food? Comfortably, three to four weeks. I’ve been seven or eight days without food—damn hungry and bad-tempered but alive. We all have reserves of muscle and fat.

“But food also dehydrates you. If you don’t have water and you find a big carcass and you start feeding on the meat, the protein is going to dehydrate you faster. You’ll want to leave the food alone.”