When you're taking tramp skills to the snow you are best to start with basic inverts. You need to build your confidence on the snow.
Find about a 20ft Jump with a nice steep tranny.
You can start off by learning a Misty 5 and a backflip. Easy to comit to and you can spot your landing. Work those for a whole day, become very consistant and start trying different grabs once you're comfortable.
Once you have those stomped go back to your trampoline and work on Misty 7's and hit up a Lincon Loop. Do those basic inverts that you're comfortable doing on the trampoline.
Give it time dude, work those 4 inverts for a while and you'll have more confidence to start getting creative.
If you have any more questions hit me with a line...