http://www.youtube.com/watch?v=aqbdxGjV1pUendofvid[starttext]By Sarah Bull Simple but sexy: Cheryl Cole wears a khaki playsuit to The X Factor auditions in Dublin today She likes to keep us guessing with her outfit choices for the X Factor auditions.And today Cheryl Cole went for a relatively simple look in a low-key khaki playsuit, which she teamed with black Christian Louboutin heels and a black cinch belt.The singer, who turns 27 on Wednesday, added extra glam with the help of some long gold earrings.But then she knew she had to make an extra effort with Katy Perry as a guest judge on the panel. Military style: She teamed the silk number with a pair of black Christian Louboutin heels and cinch belt Katy, predictably, opted for all-out glamour in a pale blue sequinned number.The 25-year-old American is the latest in a string of guest judges adding a bit of oomph to proceedings in the absence of Dannii Minogue, who is on maternity leave.And the California Gurls singer was thrilled about the prospect about using her musical talents to help others, tweeting earlier today: 'X FACTOR DUBLIN!!! Can't wait to spot a star!!!' Sparkling in sequins: Katy Perry shone in a shimmering blue dressCheryl and Katy were joined by fellow judges Simon Cowell and Louis Walsh as they hit the Irish capital, and Walsh, for one, was thrilled that the auditions were including Dublin.He said: 'I really want the winner to come from Ireland this year. This is the seventh series and it's high time. Big signing: Cheryl Cole gives her autograph to a fan outside the the Dublin Convention Centre In the spotlight: Guest judge Katy Perry also paused to sign her name for fans'The show hasn't been here since 2006. Simon said I better make it worth his while!'Meanwhile, Kylie Minogue has revealed she would love to make a return to the judging panel. New panel line-up: Katy and Cheryl pose with fellow judges Simon Cowell and Louis WalshKylie joined sister Dannii in the judges houses' stage of the reality show last year, and proved a huge success as she helped her sibling put through acts including Stacey Solomon and Lucie Jones.She told This Morning: 'Do you know, it was really much more personal than I thought it would be, with these girls in front of you with real emotion and so much riding on it. 'I found it really difficult. But if I could do the same with Dannii again this year, I definitely would.' ain man: Simon Cowell arrives at the Dublin Convention Centre [endtext]
