I think joe_dirt has the idea here. Recommend learning a backflip first to get the feeling of being inverted.
Also,a misty 5 is the same trick on the tramp but I think feels very different from a switch rodeo on snow.
The way I learned was to do a few switch 5's, then start opening up my lead shoulder and slightly dipping the other shoulder. Don't force being too inverted at first, you'll get there if you do a few. Really important, as a few people noted, to not throw it early, and don't throw it hard. It's a floaty trick, trust that it'll come around.
Best of luck!