A few tips that helped me. It took me a good few months before everything clicked all at the same time, so just keep persevering and eventually it will come naturally rather than having to think about each thing.
- Ride ALL the way to the top before even thinking about initiating the twist.
- Keep legs locked tight. This will stop you from ripping your feet out of the bases hands (ripping your feet makes your legs bend and encourages you to dive into the twist - looks really sloppy and can make you over rotate).
- Don't whip your arms around your body to use momentum to pull you around, for the same reasons as above. Think of the twist as switching the hips 180 degrees and just looking over your shoulder, rather than swinging round. If your legs are locked properly and your head turns then the twist will be completed by the whole body in a straight line, rather than in two halves (lower body then upper). This is the thing that took me the longest to get right, mostly because we'd been actually taught to whip our arms. I didn't realise I was doing it wrong until I went to a camp and immediately improved!
- Try to relax and don't pull so hard, you should take the whole time to twist slowly and gracefully.
It's a lot of things but they all kind of click together with practice. Don't panic while you're in the air, just let your body take over and it will come:) I hope any of this helps!