On the main stalk there is the large on/off switch. At the end is a rocker switch. If the main switch is off then nothing happens when you use the rocker. If the main switch is on, then when you are at the speed you desire, then you press the bottom rocker switch (labelled SET) and this activates cruise control. You will stay at this speed (going up or down hills) unless you: Turn the main switch off, or press the clutch or brake pedal.
Whilst in cruise mode, you can tap either rocker switch to increase/decrease the cruise control speed. Pressing the accelerator pedal whilst in cruise mode will obviously increase speed, but if you release it, it will settle at the last stored speed (until cruise if stopped with the switch/clutch/brake).
And finally, if you
do break cruise control, then as long as you havent switched the main switch to off, then pressing the top rocker switch resumes the car to the last stored speed.
I think I've covered all the bases. Oh and it will take a while to get used to the fact that indicating is super smooth because of the new stalk