Credit: Jamie McCarthy/WireImage

She looked amazing in a Jay Mendel dress at the Elton John AIDS Foundation Academy Awards Viewing Party in L.A. Sunday night, but just how long did it take Kim Kardashian to get ready?

"About three hours," Kardashian, 30, tells "But not continuous. I stopped and ate, made some calls -- it was a lazy three hours."

The starlet said she actually picked out her Lorraine Schwartz sapphire earrings before deciding on the navy gown, noting, "when you play around with all of the jewelry and find the right dress, it just works out!"

But of course, the Kourtney and Kim Take New York star pointed out that the evening wasn't just about fashion.

"When I was a little girl, one of my mom's friends passed away from AIDS, so from a really young age, we became very well aware of the disease," said Kardashian. "It’s really cool that Elton puts his name with a cause that is so close to his heart. The glitz and the glam is fine, but when you come to an event with a good cause, it makes it even better!"