How do you find a quote in a story?

If you quote someone within a quote, use single quotation marks and follow the same rules. He began to tell us the story, "As soon as I walked in the room the principal said, 'You've been here a lot lately John,' so I just sat there quietly."

The quote within the quote, Do unto others as you would have them do unto you, is enclosed in single quotation marks. (The British convention is the opposite; the main quote would use single quotation marks and the quote within the quote would use double quotation marks.)

Another words, look for the quotation marks.