I recall starting out when i'd spin I'd throw my head and that would send me off axis. Then I was riding pipe and a snowboarder mention the turn with their hips in the air. So I started spinning with my hips and it came perfectly. Plus it gives you a solid foundation for adding grabs to your spin because you can look back at your tail, for instance, to grab a reverse tail and still maintain your spin. It is ver important though, cannot stress or repeat it enough, to get your pop. If you have a solid skiing form you know how to ride weight forward, shins pressed into the boots weight on the balls of you feet and heels in the back of you boots and hands in front. I started learning to spin by using a mogul skiing stance, just widening the feet a bit to get the feel down. Once you get the pop and the spin you won't have to think about it as much, I remember all I needed to do to become fluent in spins was to land my first three. I think pre-winding is a bad idea. It causes you to spin before the lip and forget to pop. Just find a jump that's big enough, 2 feet of the ground and 5 feet of travel is NOT big enough. You don't want to have to huck it, that will not give you a feel for the spin or what you are doing. Watch ski videos, even watch some snowboards to see how they spin. focus on you pop, even if it means putting the video on slo-mo standing up in your living room and "shadow" jumping. Focus on your weight forward, get in your ski boots and lean forward practicing your pop. I know these sound a bit extreme, but you'll do lots of crap like that in any other sport ... and it does help.
