OK - just checked my handbook.
First, check that all of your tyre pressures are correct.
Assuming they are, press and hold the button on the end of the indicator stalk. When "SET/INFO" appears, keep repeatedly pressing it until the "RESET" options appears (with a "flat tyre" icon and an exclamation mark in the middle). Then press (and hold) the stalk button until the display changes.
That's all the handbook says (so not actually sure what it should "change to" - I imagine back to the SET/INFO screen) - the book then basically adds, "drive off".
After X amount of time/miles driving, these pressure levels will be set as the norm, and the run flat indicator should reset itself and the warning light will disappear.
Hope that helps.