I can't do them but I coach tramp and I'm all about working up to stuff.
The way I would do it is first I'd say find a jump where you can really float the sw cork 5 also make sure you have no problem spinning big on it (ie be able to sw 10).
Then, now this requires good spacial awarness and body control, I would set the sw cork 5 as hard as you can with still being able to super open up and still land at 5.
Do that repeatedly and really focus on how much air time you have and what would happen if you went with the intial spin you gave it, it'll also give you a good referance point to focus on where to start your second cork, aka, your almost at the 5 and super opened up and your still 6 feet above the knuckle you can ask your self do I have time for a cork 3 still.
Hope that helps! I would highly suggest being good at dubs before trying this like on a tramp of off a diving board