short version of chromium's post is:
it's all completely automatic, just drive it, same with traction control if fitted, just happens, can't turn it on and off, it just does it.
Hil descent control has to be switched on and off though.
if you don't have the manual, you could search for Rave CD, which is a cross between haynes manual and owners manual, all the owners manual info is in it.
good luck and welcome, the forum is a bit lively at times, but thick skin will get you all the answers you need.