Zara Phillips and Mike Tindall at darts final

Zara, 30, quaffed champers as she joked around with rugby ace hubby Mike, 33.

He made her laugh by donning a beard, sunglasses and trilby hat "disguise" before holding up a "180" sign at the Alexandra Palace in North London.

The pair watched from the VIP area as Adrian Lewis, 26, beat Andy Hamilton, 44, to retain his PDC world darts crown, scoring eleven 180s.

Royle Family star Ralf Little, 31, held up a sign saying: "Mike Tindall is behind me!! Wow!"

David Williams, of event sponsor Ladbrokes, said: "Mark and Zara are big darts fans. The crowd held up signs asking how Prince Philip is."

Judges arrive for X Factor final

Louis, in a black Mercedes, was the first to arrive, followed by sharply-suited head judge Gary.

The pair stopped and chatted to fans before Tulisa stole the limelight in a gorgeous teal dress.

The N-Dubz singer took the opportunity to drum up support for her act, shouting "Vote Little Mix" as she made her way towards the entrance to Wembley Arena.

She shivered as she took the time to greet fans, even stopping to look at a photo of herself on one teenager's mobile.

After a lengthy wait, diva Kelly was the last to arrive, decked out in sky-high stilletos and a short black dress.

But she made it up to the crowds by chatting and posing for pics, even running back for another photo as security staff tried to drag her inside.

Charlotte Buckland, 16, who travelled all the way from Newcastle without a ticket in the hope of seeing her favourite act Little Mix, said the red carpet experience was well worth the journey.

The thrilled teen gushed: "It was amazing!

"Tulisa looked so stunning and spent loads of time talking to fans.

"I was hoping Little Mix were going to come out for a photo but even without that, this has made my year."

The crowds were unable to get a glimpse of their favourite acts, who were already preparing inside the arena.

Tonight's show will see Little Mix, Marcus Collins, and Amelia Lily duet with the judges in a last bid to take the X Factor crown.

Kelly and Amelia will sing Ike and Tina Turner's River Deep, Mountain High, while Tulisa and Little Mix will perform a medley of Alicia Keys hits.

Marcus and Gary are performing Billy Joel's She's Always a Woman.

X Factor hopefuls head off for the final

The teenager from Middlesbrough was seen leaving her London hotel this morning alongside her show rivals ? Little Mix and Marcus Collins.

The youngster showed little sign of nerves at the prospect of performing live in front of 12,000 people at the iconic arena tonight.

Wrapped up against the winter chill in a pink jacket and clutching a similarly-coloured mobile phone and handbag, the hopeful cut a confident figure.

The Little Mix ladies also ensured they didn't get a chill before the biggest night of their lives by wrapping just as well.

Jade, Perrie, Jessy and Leigh-Anne looked calm as they made their way to waiting cars.

Simon Cowell's plot to turn them into the new Spice Girls may have settled their nerves.

Stars in the making ... Little Mix's Jessy and Leigh-AnneFLYNET

Even if the quartet fail to win the show, the svengali will hand them a record deal worth millions as part of a masterplan to make them stars on both sides of the Atlantic.

A source told The Sun: "Simon is thrilled by the quality of this year's finalists ? but he's extra excited about Little Mix. He genuinely believes they could be bigger than The Spice Girls.

Meanwhile show favourite, crimper Marcus Collins paid tribute to his home town by wearing a hoodie with the word Liverpool written on it.

The contestant's early departure will please fans at the north London venue.

Some had even camped through the night to be the first to catch a glimpse of them.

And as temperatures sank to near freezing last night a pair spoke of how unprepared they were for the conditions.

Best friends Chloe Darson and Chloe Parr, both 16, were the first to arrive at Wembley Arena at 6pm yesterday after travelling to London from Lincolnshire.

"I just had this one little blanket," said Darson. "We didn't know we had tickets until yesterday when my friend said she had spares so we just left really spur of the moment.

"We decided to camp out to make sure we get good seats. We haven't been lucky enough to go to any of the other shows so we wanted to get here early for the final.

"It has been freezing."

Parr added: "I really didn't bring enough warm stuff. I just found out we were coming yesterday so I left work and jumped straight on a train to London. I'm absolutely freezing right now."

Shreya Kanani, 19, a dentistry student in Leeds, left her warm bed at 4am to join her friends in the X Factor queue.

"We are so cold," she said. "People's parents have been coming every couple of hours and bringing water bottles and extra blankets and socks. Other than that we've just been snuggling up to keep warm.

"It'll be worth it though. I had an exam on Friday and I couldn't concentrate I was so excited."