It’s very easy for us to get lost in the woods. Science has discovered that people are constitutionally incapable of walking in straight lines when they don’t have markers they know how to follow:
A Mystery: Why Can’t We Walk Straight? from NPR on Vimeo.
So it’s helpful to learn how to track and trail, and how to use natural features as “handholds” so you have a sense of how you fit in the landscape. The technique ranges from dead-simple to highly complex, beginning with the easy part: pick a relatively distant, immobile feature (mountain, bump in the landscape, really big tree on the horizon) and determine which direction you want to go, relative to it. Now, as you travel, just keep that feature in sight at about the same angle to your body as it was when you picked your direction. So if you think you should go straight ahead and there’s a distinctive mountain top off to your right, keep it to your right as you walk. Remember to reassess periodically and pick a new feature, or you will manage to walk in a beautiful circle all around that mountain…
When I teach my wilderness skills and survival classes, I always say the number one thing to do if you get lost or find yourself in a frightening situation is: “sit down, and have a snack.” You need to get out of the cycle of self-doubt and settle your judgement, as well as boost your energy for the challenging decisions you’re about to make as you try to get found or simply stay safe. And if you’re sitting down, you’re resting and you can hydrate, check your map, rearrange your gear, or clean the dirt out of your boots. These are all useful survival activities! Now science comes along to support my advice:
The brain, like the rest of the body, derived energy from glucose, the simple sugar manufactured from all kinds of foods. To establish cause and effect, researchers at Baumeister’s lab tried refueling the brain in a series of experiments involving lemonade mixed either with sugar or with a diet sweetener. The sugary lemonade provided a burst of glucose, the effects of which could be observed right away in the lab; the sugarless variety tasted quite similar without providing the same burst of glucose. Again and again, the sugar restored willpower, but the artificial sweetener had no effect. The glucose would at least mitigate the ego depletion and sometimes completely reverse it. The restored willpower improved people’s self-control as well as the quality of their decisions: they resisted irrational bias when making choices, and when asked to make financial decisions, they were more likely to choose the better long-term strategy instead of going for a quick payoff.
So while it’s no substitute for the many other things you should know how to do or for pure common sense and survival instinct in terms of getting through a sticky situation in the woods, just remember that science backs it up: when in trouble outdoors, first thing to do is sit down and have a snack.
Eliza F. Cava 
Also applicable if you find yourself lost in residential Montevideo!