try dub cork twleves and then break it down to cork sevs
nah but seriously, if you wanna cork 7, learn 7 and then cork em
the best way is to try them on trampoline cause if youy try it first on snow you will break your back...and you can also try them on diving board(switch cork).
the basic try before it is back flip and the spin(540,720,900) and i suggest you to try bio so you can get the feeling of offaxis spin but a lot of people learn cork before bio
If you're comfortable with your 7's, start with cork 7's. Find a nice 30ft table. When spinning left, slightly dip your left shoulder on a 7 until you get used to the feeling of going barely corked. Once you get used to the rotation, you can try more and more corked. Good luck.