Adweek: Evan Spiegel admits to being a little nervous ahead of his first trip to the Cannes Lions International Festival of Creativity. That’s understandable. At 25 — an age when many college grads are still backpacking around Europe — the founder and CEO of Snapchat has been given top billing at one of advertising’s biggest events. “Anytime you do something for the first time, it’s nerve-racking,” Spiegel confessed just ahead of his trip to this annual gathering for the advertising elite on the French Riviera. “And I’ve never built an ad business before.” When he takes the main stage at Cannes, 6,000 of the agency world’s top creatives and deal makers will be eager to hear his pitch.