Jessica Simpson on Her Wedding: 'Don't Have a Dress Yet'

Singer-turned-fashion designer Jessica Simpson talked with "Extra" correspondent Terri Seymour about her upcoming nuptials with fiancé Eric Johnson - and how she's more focused on her new NBC show "Fashion Star" than anything else.

"I don't have a dress yet," confessed Simpson yet she added, "The dress is going to be amazing. With a wedding, it should be a celebration like we should all be having fun, every single person there."

As for the wedding date, Simpson laughed, "I've heard people throw around dates and not one of them has nailed it. Not even close."

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For now, the successful fashion designer is gearing up for the new reality show, on which she'll be a mentor to aspiring designers and will help guide contestants as they compete for a multimillion-dollar contract to launch their own brand.

"It's a fun show to be a part of and we all get to dress up," smiled Simpson.

"Fashion Star" premieres this fall on NBC.