If you're lost in Central Park, head for the nearest lamp post.
Chances are, it will look like one of these: The first pair of numbers indicates the closest cross-street; the last two digits are Park serial numbers.
The old lamp post on the left tells you that you're near 71st Street; the newer, less gracious, model on the right shows that you're closer to 72nd Street. With that in mind, you can find a landmark (skyscrapers, statues, ball fields), head west into the sunset, or follow the traffic on the foot path if it's rush hour. Odds are, you'll reach either Fifth Avenue or Central Park West and can move on from there. The Park is also full of good maps and helpful pedestrians, so don't be shy.
Here's a helpful landmark. He towers above the Park and can be seen from a distance. If you see Daniel Webster's face, you'll know you're pointed west toward 72nd Street.