It’s been said that the best way to get a party started is to bring your friends. That’s exactly how the Met Gala , fashion’s most coveted invitation of the year, became fashion’s “ party of the year.” The planning began in 1944, when Dorothy Shaver, then chairwoman of the Costume Institute ’s event committee, along with Eleanor Lambert and friends, began what is now one of the most successful fundraisers for fashion exhibitions. The dinner and dance was initially held at New York City’s Rainbow Room and the Waldorf-Astoria until the Costume Institute officially opened its galleries inside the Metropolitan Museum of Art in 1959. After Shaver and Lambert came Diana Vreeland, who joined the Costume Institute in 1972 as a special consultant for exhibitions. Vreeland transformed its exhibitions and, in 1975, with the help of socialite Pat Buckley, elevated its annual party into fashion’s most prestigious event.…