Confessions of an Advertising Man, by David Ogilvy

Sure, you can (and should, because it’s hilarious) actually buy a copy of Sterling’s Gold, the fictional memoir by Roger Sterling from Mad Men. But you should also read the book that filled Sterling with so much envy—Confessions of an Advertising Man, by advertising legend David Ogilvy. It’s basically an instruction manual in which Ogilvy shares the lessons he’d learned from decades in the business, and it established him as a kind of Ad Guru for the 1960s. If you want insight into how real "Mad Men" thought, this is the book for you.