How do you change the time for a BMW to 24 hour format?

I have a 2002 325i BMW, I figured out how to change the time, by turning the right knob on the dashboard, but I cant seem to be able to change it to 24 hour format. Do I push the button or do I keep turning the little knob even after I reach 12:59?How do you change the time for a BMW to 24 hour format?you press in the right side button, same button you use to change the time (minutes/hours)How do you change the time for a BMW to 24 hour format?you hold it.