The team of seamstresses working on Kate’s Alexander McQueen gown washed their hands every 30 minutes, to protect the brilliance of the pristine lace and threads.

Another mistake was less noticeable, but quite impactful for the nervous young bride—she accidentally spilled perfume on her famous dress. Rosalind Coward details the incident in her 2004 book Diana: The Portrait, where she interviews Diana’s wedding-day makeup artist, Barbara Daly.