For any task you might want to do, there’s a right way, a wrong way, and a way so monumentally bad that no one would ever try it. ‘How To’ is a guide to the third kind of approach. It’s full of highly impractical advice for everything from landing a plane to digging a hole. Bestselling author and cartoonist Randall Munroe explains how to predict the weather by analyzing the pixels of your Facebook photos. He teaches you how to tell if you’re a baby boomer or a millennial by measuring the radioactivity of your teeth. He offers tips for taking a selfie with a telescope, crossing a river by boiling it, and getting to your appointments on time by destroying the moon.