This textured knit jumper from ASOS should be it.

It’s got that great slouched Stella McCartney thing going on that’s just always going to be cool. Wear it over something long and floaty, maybe even pleated, for that early Marc Jacobs silhouette. Alternatively just wear it with some great skinny pants, clunky wooden heels and finish it all of with a statement piece of jewellery. Preferably something Lanvin; big, beautiful, shiny and with grosgrain involved. A jumper like this can handle a bit of glamour thrown at it. (If Lanvin jewellery isn’t something your monthly pay cheque allows then it’s time to distract your Grandma with a cuppa whilst you rummage through her jewellery box.)

And also, I in no way condone this model’s hair. Just saying.