The answer is simple: Sleep naked with your partner. According to USA Today, a survey was conducted where a researcher suggested that sleeping naked would improve sexual satisfaction among couples. The survey, which consisted of mostly white subjects over 35 years of age, found that just 34 percent of U.S. women and 38 percent of U.S. men sleep naked with their partners.
A conclusion can be drawn here, and no, it's not "white people don't sleep naked"—it's that more sex between couples and easy access to it will make for happier people. Seems simple enough, right?