The 'Murder On The Dancefloor' singer said she'll be listening to the instructions her professional partner gives her and working hard to improve her technique.
Sophie said: "I'm quite competitive with myself – I'm not a competitive person with other people. I'm actually quite a good little pupil really, a goody goody. So I will work as hard as I can. I respond better to people that recognise that, rather than saying 'that wasn't it', because I promise whatever I do I will be trying my hardest.
"There's no point doing it if you don't, so I want someone who is supportive of that. I think it can be worse for someone's motivation if you're too hard on them."
The mother-of-two doesn't currently rate her dancing skills that highly when it comes to choreography, saying: "Are we talking freestyle dancing with my mates? I'd probably put myself at 6 or 7. I'm not a bad person to be dancing with, I go for it. I keep changing my moves every few beats. I'm certainly enthusiastic, and always smiling.
"In terms of choreographed dancing - I'm probably closer to a 2 or a 3…"
Sophie added she already has a gameplan for the dance floor - getting into character. "Use the costume and the make-up and the whole experience. If I thought of me as 'the me at home' doing the dancing, it would be so scary and ridiculous. I'd probably be stuck in my tracks. If I imagine it more like I'm playing the part, then I think it will help me get through the nerves a little bit more. We'll find out!"
Strictly Come Dancing starts 7 September on BBC One
The Strictly Come Dancing lineup in pictures:
Copyright: BBC Ray Burmiston
Watch the first trailer for Strictly's new series below: