In addition to the basic requirements for setting up a maneuver, ie;... safe altitude, clearing turns, radio call, emergency field..etc..
Set it up like you were in a traffic pattern turning base to final, (this is typically the most common area for this to happen), have an area selected on the ground to simulate the landing environment.
As you simulate overshooting the turn base to final with a constant 30 degree bank, maintain that 30 degree bank and use rudder to bring the nose of the aircraft around to correct for the overshoot. As the nose swings around, use aileron to counter the rudder effects and as the nose pitches down as a result of loss of lift, add back elevator to maintain altitude. So, turning a left base to final, you'll have too much left rudder, right aileron and too much aft elevator....the buffet will prompt you to recover.
This particular stall seems to be the result of instructors putting a bank limitation on their students while in the pattern. If you tell a student not to bank more than 30 degrees in the pattern, they won't.....instead they'll use rudder to compensate.
I wouldn't attempt to demonstrate any maneuver, especially the crossed-control stall, for the first time on a checkride. If you take it beyond imminent, it will break fairly violently, almost to fully inverted. It can be surprising the first time you see it.
Definately practice practice practice before your ride. make sure you know the setup and the way the maneuver should look. This one is a biggie to know because before you know it you will be with a student trying to turn you into twisted metal. I had one guy who i thought was good to go on landings and I got a little overconvident in his abilities, before i knew it we were base to final and about to spin into the ground. Never trust your students completly and always be ready on the controls.