Nicole Richie lets her mood dictate her style.

The 30-year-old party girl-turned fashionista is a regular on ''best dressed'' lists, but admits how she dresses depends on how she feels.

Talking about choosing clothing for her role as a mentor on US reality show 'Fashion Star', she said: ''It all depends on my mood for the day that I'm filming. I don't have my outfits planned out at all, it really just depends on my mood and where I am on that day.''

The former wild child - who has daughter Harlow, four, and son Sparrow, two, with husband Joel Madden - wowed in a metallic print floor-length vintage dress with Christian Louboutin mules on Monday (26.03.12) night's episode, and admits she leant the dress from a friend and had it altered in the hope she wouldn't ask for it back.

Talking to US Weekly, she confessed: ''I actually borrowed [that dress] from a friend and I tailored it to fit me on purpose, hoping that she'd let me keep it.''

When it comes to her own career, Nicole cites dad Lionel Richie as being her biggest influence.

She explained: ''I would say my biggest mentor has been my father, because he always has been - actually, both of my parents have always been ones to encourage me to be myself and stay true to myself and not fall into what other people want me to do.

''And it is important not to copy other people's careers but kind of set the tone of who you want to be and my father's always encouraged me to do that.''