I am such a huge fan of contrasts.
For me, it's good contrasts that fit together (as contradicting as that sounds) that really makes a great outfit.
This editorial from Elle Norway's February issue has some great examples of what I mean.
Edgy leather + feminine silk.
Clean white + animal print.
Black + white.
A baggy t-shirt + elegant heels.
Elle Norway February 2012
Photographer: Åsa Tallgård
Model: Siri Tollerod
Stylist: Petra Middelthon
Image Source: Fashion Gone Rouge