EXCLUSIVE VIDEO: Countess Luann de Lesseps Chooses A Royal Wedding Gown For Kate Middleton

From New York City housewife to singer, actress, and now -- royal personal shopper!

Countess Luann de Lesseps knows a thing or two about what it takes to look regal, and as reality TV's most famous royal she takes RadarOnline.com shopping for the perfect wedding gown for princess-to-be Kate Middleton, who she thinks is going to "surprise us" all on the big day.

The Class with the Countess author arrived at Beverly Hills' famed Renee Strauss bridal salon (decked out in a watercolor Teri Jon ensemble) to select her top three choices from an array of uniquely stunning European designers -- and give Kate the dress do's and dont's for her nuptials on Friday, April 29.

First pick of the day -- a nod to Princess Di -- from the front to the back.

"I love the long sleeves," the Countess said of the Complice creation.

"It's an homage to Princess Diana who wore long sleeves. It's traditional and has the beautiful full skirt.

"It's a dress fit for a princess... and the silk taffetta is gorgeous. This is actually the first choice of the royals because it's very light and can be worn all day long.

"And everyone remembers Princess Di's train on that beautiful day. This is perfect for Kate!"

Second on her 'I do' list, a silk taffeta ruched strapless Marina K. gown with a princess skirt, of course: "It's  a modern sillouhette and I find it classic and perfect for Kate because she's a very classy lady and she has a great figure."

And last but not least, the Countess' choice comes with a touch of shine and plenty of textured tiers: "This has the luxury of layers," she said of the Liancarlo silk organza and English tulle gown.

"It has a detachable belt which makes a nice waistline. It's a simple dress and if she's going to wear a tiara this won't clash. This says princess!

"I think Kate has her own sense of style and she carries herself beautifully well. I think she'll go traditional, but she will have her own modern edge and I think that'll be interesting because people are expecting her to be a certain way and I think she's going to surprise us."

From 'I do's' to 'I don'ts', the Countess said a gown with too much sparkle on top will "clash with the royal jewels," of course.

And what did she think of a platinum-colored gown? "Leave that for the wedding ring," she said.

Everyone has seen that Kate knows how to show off her svelte figure, but the Countess says not when walking down the aisle. "This is perfect for the wedding on the beach... save see-through and skin for after the wedding."

And black and white should be saved for the photo album: "It's way too full, it's a party dress... and it makes me want to go cha-cha-cha."

A princess wouldn't be complete without her jewels, so with some help from Renee, the Countess had fun singing Here Comes the Bride while playfully trying on baubles from Renee's treasure chest of sparkles: "It just wouldn't be the same if she wasn't wearing a tiara," the Countess said of the soon-to-be real-life princess.

And who could forget Prince William -- something old, something new, something borrowed, something blue -- garter belt, that is.

After playing dress-up, Luann couldn't help but feel inspired: "It just makes me want to get married again!" she exclaimed with a smile, as the ladies toasted with a glass of champagne.

Season 4 of The Real Housewives of New York City premieres Thursday, April 7 at 10 p.m. on Bravo.