I just learned these last week after no less than 30 tries, so I know what you're feeling. I watched every attempt on video, and it's really kinda hard to judge what you're doing wrong without video. What I found was that the harder I set the spin, the closer I got to landing it.
The day after I watched the film, I tried it a couple times setting it harder and harder to the point where I almost went inverted. That time, the spin came right around and I was so stoked to see the ground below my feet instead of landing on my right side like I did about 30 times before.
Try to set the spin hard. Think of setup as almost rotating your right shoulder down to your left knee.
Here's a vid of my first time landing it. Not the best looking....