Warren Buffett, the billionaire chairman of Berkshire Hathaway Inc., advised aspiring entrepreneurs that satisfied customers are essential to building a business.

“Tomorrow morning, when you look in the mirror after you’ve gotten up, just write — put it in lipstick, or whatever you want, on the mirror — just put, ‘Delight my customer,’ ” Buffett told the crowd of more than 500 assembled at LaGuardia Community College in New York.

“Not ‘Satisfy my customer,”’ Buffett added. “Delight my customer.”

Buffett has long highlighted the importance of enduring business relationships, and he reiterated praise Tuesday of Amazon.com Inc. founder Jeff Bezos as an executive who earns and maintains the loyalty of shoppers.

Speaking at an event sponsored by Goldman Sachs Group Inc. to celebrate graduates from a program to educate small-business owners, Buffett highlighted how word of mouth can build a reputation.

“Any business that has delighted its customer has a sales force out there that you don’t have to pay,” Buffett said. “You don’t see them, but they are talking to people all the time.”