Per my manual - and this link
http://cache.bmwusa.com/PDF_6117e873...e-107286b35189
Activating SPORT+:
Press button repeatedly until SPORT+ appears in the instrument cluster and
the DSC OFF indicator lamp lights up.
Indicator/warning lights:
SPORT+ is displayed in the instrument cluster. The DSC OFF indicator lamp lights up.
You can *also* turn off DSC with the DSC button, but - unless there's something I'm missing - Sports+ turns it off as well. Given I got the car totally sideways at T11 and T15, pretty sure it's all the way off