Jeff Bezos and Lauren Sanchez

Lauren Sanchez Bezos tied the knot with billionaire Jeff Bezos Friday in Venice, Italy amid a grand gallery of celebrity guests and an ongoing party in the city ... and she's revealing a hint about her "something blue" wedding keepsake for the big day -- fittingly, it has to do with her now-official hubby's space company Blue Origin ... though she's choosing to be demure about it.

Lauren shares in an interview with Vogue -- during a fitting for her wedding dress -- she and Jeff were keeping to a few traditional aspects for their grand nuptials ... one being a secret souvenir she brough along during her 11-minute, female-filled Blue Origin trip to space.

You may know the old phrase instructing brides what to wear for good luck in their marriage ... "Something old, something new, something borrowed, something blue." The "something blue" a bride-to-be is supposed to wear in the ceremony should be an item that reflects the color of purity, love, and fidelity ... and it's meant to ward away evil.

Only the star-studded wedding of Jeff Bezos and Lauren Sanchez Bezos could make Paris Fashion Week look like an also-ran of who's who.

Over on the Boot ... the billionaire and now-bride were living it up with 200 of the richest and powerful people on the globe ... while over in City of Light, stars who did not land a wedding invite were strutting their stuff.

Paris Fashion Week participants included the likes of Rihanna, Sabrina Carpenter, Tori Brixx, Rich The Kid, Duarte and Delphin Musquet -- certainly no slouches in the world of fame!

Lauren Sanchez is tacking "Bezos" onto her last name ... sharing a pic of herself in a gorgeous white wedding dress and changing her name on IG.

The star -- who held a wedding ceremony to Amazon founder Jeff Bezos on Friday in Venice, Italy -- shared the first look at the gown on her IG ... and changed her screenname to "Lauren Sanchez Bezos."

She also wiped her IG clean ... a fresh slate for the newlywed as she heads off into married life.

Jeff Bezos and Lauren Sanchez are sparing no expense for their wedding guests ... tossing them some great gifts -- which also happen to be a great advertising opportunity for Amazon.

Sanchez spoke to Vogue in an article published after she shared a photo of her wedding dress Friday ... and, she gave an inside look at the goodie bags she and Jeff gave to their guests.

LS told the outlet she and Bezos wanted their guests to feel comfortable while wearing their new gifts ... revealing all the dudes are going home with Vibi Venezia blue velvet Venetian slippers -- and, the women are getting black open-toe slippers from Amazon.

There has been rampant speculation about where exactly Jeff Bezos and Lauren Sanchez would say their "I do's" for the epic days-long celebration in Italy ... and now we know it was all well-"staged."

Aerial snaps of Venice's historic island of San Giorgio Maggiore showed a portion of the ceremony took place at Teatro Verde -- "Green Theater" -- close to the edge of the tiny island.

See for yourself ... it's clear a massive structure was constructed for the event -- and it was more than big enough to hold the 200 superstars invited to celebrate with the couple.

Kylie Jenner, Oprah, Usher and Bill Gates are ready to see some amore in Italy ... because they're piling into boats on the Venice canals en route to the wedding ceremony for Jeff Bezos and Lauren Sanchez.

It's a who's who of Hollywood celebs and billionaires Friday in the Floating City ... and ya gotta see how Jeff and Lauren's famous friends are dressed up for their big day.

Kylie, Oprah, Ellie Goulding, Kim and Khloe Kardashian, Jewel, Karlie Kloss, Ivanka Trump and Kris Jenner are putting on for the ladies ... and they're all glammed up.

Orlando Bloom is playing it cool at the Jeff Bezos and Lauren Sanchez wedding ... he's single after splitting from Katy Perry, but we've learned he's not trying to hook up with other wedding guests.

Our sources tell us Orlando is being very guarded in the way he's dealing with women in Venice ... even though he's around some very sexy, single and eligible celebs.

Orlando's in the midst of party central at The Gritti Hotel in Venice ... but he's mostly been bro'ing out with Tom Brady, Leonardo DiCaprio and Scooter Braun.

The weather is currently clear in Venice, Italy, for Jeff Bezos and Lauren Sanchez's mega wedding ... but Kylie Jenner is ready to steal some thunder!

Superstar guests are currently making their way to the lavish ceremony on the historic San Giorgio Maggiore island ... and it sure looks like Kylie is on her way to turn some heads.

KJ posted a short vid on her IG Story just a few minutes ago aboard a boat we presume is on the way to the island ... looking pure fire in a cream and white-colored corset totally highlighting her assets.

Tom Brady, Leo DiCaprio, Orlando Bloom and Sydney Sweeney are in the thick of party central at the Jeff Bezos and Lauren Sanchez wedding in Venice ... and it sounds like Tom's making a move.

We've learned the most hopping place in the Floating City is The Gritti Palace ... a landmark waterfront hotel where a collection of Jeff and Lauren's most famous friends are staying -- and it's the place to be for wedding guests looking to party.

Sources who are there tell us Tom, Leo, Orlando, Sydney, Jerry Seinfeld, Oprah, Charissa Thompson and the Kardashians are all staying at the Gritti ... and Sydney is the "center of attention" for single guys, including TB12.

Jeff Bezos is keeping it classic on his wedding day ... because he's rocking a tuxedo.

Check out these photos of Jeff before his star-studded wedding to Lauren Sanchez Friday in Venice, Italy ... dude's looking dapper.

Bezos is smiling and waving ... pairing some circular rimmed sunglasses with his black-and-white tux.

Brooks Nader is arriving in Venice in style ... stepping out in the Floating City on Friday wearing a black dress that fits her body like a glove!

Check out our gallery -- the Sports Illustrated Swimsuit model is heating up the town ahead of the luxe Bezos-Sanchez wedding ... giving a glimpse of her chest with an ultra-low neckline.

She's pairing the daring dress with a white clutch, black sunnies and black strappy sandals. She's all smiles ... seemingly not worried that all eyes are on her as she rides off in a water taxi.

Tom Brady and Orlando Bloom are making it easy for all the single ladies in Venice ... with the two bachelors cruising around town in the same water taxi ahead of Jeff Bezos and Lauren Sanchez's wedding!!

The NFL G.O.A.T. and British actor kept it casual as they hopped in a boat together on Friday ... with TB12 rocking a white shirt, black shorts, green hat and some Nike sneakers -- and Bloom electing to bare his arms with a black tank and shirt and white shorts.

The hunky stags were accompanied by friends -- including Scooter Braun and Alex Spiro -- for the ride through the canals ... although it's unclear where exactly they were headed.

Jeff Bezos and Lauren Sanchez can't buy everything in the world with Amazon money, it turns out ... 'cause the island they're getting married on isn't closed completely!

Sources with direct knowledge tell TMZ ... businesses on one side of the island of San Giorgio Maggiore -- including two museums, the sailing club and a café -- are open all day and will close at normal times, and the side of the island they're on won't be shut down for the event.

However, the islet is set into two pretty distinct parts ... with one half covered by businesses and the other dominated by the wedding grounds and the Teatro Verde amphitheater, as well as sprawling greenery. It's unclear whether the Basilica itself -- where the couple is reportedly going to take their vows Friday -- is open to the public during the daytime.

Lauren Sanchez is showing off major BLING before her star-studded wedding to Jeff Bezos Friday in Venice, Italy ... we're seeing a close-up shot of her flashing two giant rocks on her digits.

The bride-to-be was photographed in Venice today with gigantic diamond rings on both her ring fingers. One appears to be a pillow-cut, the other -- on THAT finger -- is an oval the size of an egg.

As you know, the impending nuptials have brought out a galaxy of stars and celebrities.

The rain in Venice brought out a beautiful sight Friday morning ... not a rainbow, but the gorgeous faces of Hollywood's A-list instead.

A few of the guests who will attend Jeff and Lauren's impending nuptials went for a stroll along the canals in Venice ... including Sydney Sweeney, who flashed some skin in a leggy and low-cut black dress.

Leonardo DiCaprio's longtime partner, Vittoria Ceretti, proved a rose by any other name is just as sweet ... even the roses on her dress -- a sweet addition to her skintight gown.

Jeff Bezos and Lauren Sanchez made it crystal clear no grumpy locals were gonna rain on their parade ... but Mother Nature had other plans, literally soaking them before their big "I do."

Catch the clip ... Jeff and Lauren got hit with a serious downpour after their Italian rehearsal dinner bash Thursday -- the billionaire holding onto his bride-to-be with one hand and sporting an umbrella in the other as they scrambled to a water taxi.

There were a bunch of security guards hovering to make sure the soggy dash went off without a hitch -- but all good, Jeff and Lauren looked totally chill as they kept the party going.