In honor of its new exhibit, “Isaac Mizrahi: An Unruly History,” the Jewish Museum hosted its first “Insta-meet” on Tuesday. Not only that, but Mizrahi himself offered a tour a few days before the show officially opens to the public. The writer Lynn Yaeger was also on hand to offer a more academic take on the designer’s playful work. But one thing that didn’t require any explanation was Mizrahi’s obvious zest for color and frivolity, all on vivid display for the fashion and social media-obsessed fans and photographers touring the halls. The exhibit runs March 18 through August 7.