Surprise Wedding 
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Yifat Oren knows how to keep a secret. Just ask Anne Hathaway—when the actress tied the knot in a ceremony that was kept under wraps from media in Big Sur in 2012, it was Oren and her team who pulled it off. Oren has planned similarly discreet wedding for a roster of A-list clients including Natalie Portman, Reese Witherspoon, and Adam Levine.

But the most top-secret nuptials she's planned, Oren says, have taken the undercover wedding a step further and kept the I Do's a secret not just from the public but from the ceremony's guests too—until the very last minute. That's right, in recent years, Oren's clients have been asking her to help them plan surprise weddings, where no one except for a few close family members and friends knows that two are about to become one, until an aisle emerges with a white-clad bride on it, flash mob style.

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It can be a magical and romantic approach to marriage for couples who enjoy whimsy, says Oren, but there are a few essential keys to nailing it.

First, choose the right date. The easiest way to pull it all off is to plan your wedding around a holiday, like Halloween, for example, and ask everyone to come over to celebrate. "Dress up in an amazing white gown. When it’s time, go upstairs, throw on a veil, and grab your bouquet. Cue the music. Super fun. Nobody would ever guess this is how a Halloween party would turn out," Oren said.

Another great time of the year? A "Christmas party invitation, which we have done. About an hour or two into the evening, you walk upstairs, change your dress, come down, and just like that, with about 150 candles and in front of the fireplace, you have yourself a little ceremony," she suggested.

Surprise Weddings
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If the holidays sound like an imposition, invite everyone over for a surprise birthday party for either you or your S.O. on a date close to the actual birthday. Once people arrive, serve cocktails and hors d'oeuvres before changing into your bridal gown.

The guests aren't the only ones who should be kept out of the loop, said Oren. It's important to keep the wedding a secret from the vendors you are working with too because they may accidentally reveal your secret early. "The last thing you want to happen is a server passing drinks spilling the beans by accident," said Oren.

Finally, make sure your closest family members and friends know that this party is not to be missed. Tell them you are going all out for your partner's birthday and they absolutely have to be there. "They would hate missing it if they knew what the surprise was," Oren added.