The 80/20 rule dictates that your stuff should take up only 80 percent of a given space — a closet, a drawer, a bookshelf — leaving 20 percent empty. Think of it as headroom for your stuff: Leaving ...

When counting squares in a grid, don’t stop at the smallest boxes; the bigger ones are hiding too. The rule is simple: In an n × n grid—where n is the number of squares both horizontally and ...