Speaking ahead of this week's first show, Dannii admitted it was "very difficult" sitting next to the Take That star on the judging panel.
"He’s distractingly good looking!" giggled Dannii, "That’s not fair, it’s a very difficult part of my job.
"And then I have Martin [Kemp] on the other side of me, so I’m wedged between two guys who couldn’t be more charming or more beautiful. Really it’s a tough job, but someone has to do it!"
The trio will be joined by a series of guest judges throughout Let It Shine as they search for top talent to star in a new stage show based on the music of Take That.
Former X Factor judge Dannii said it was "important" for the show to be offering more than just instant fame.
She explained: "It’s a job and a set of skills that they can use forever. That’s incredible. They are going to be travelling the country and you have to get a lot of shows under your belt to get good at what you do.
"With the level of talent we have got, when we do get our final five, they won’t just be winners of this show - I think they have a huge chance of going on to be superstars. That’s how high the standard is."
As for the stage show itself, called The Band, Dannii teased: "I know everything about the show, but I can’t say anything!
"It’s so exciting and will be totally unexpected. I love what the whole show is going to be about. Having it explained to me fully, I was moved from tears to laughter just sitting there while he was talking to me about it. So once they get all the right performers in that show and get it up and running, it’s going to be incredible."
Let It Shine begins on Saturday night on BBC One from 7PM.