Before they turn, they usually have a preparation position in which feet are at CBMP, and upper body at torsque. A nice CBM enables the dancer to have momentum to turn plus letting the body to have the maximum of body turn without head turn. The turn is actually initiated by the 'unwinding' of the body at its CBM, until the body can turn no more the head needs to be turned so as to make a full turn. The final head turn is more like a slap than a turn. And it could be the hardest part for beginners to handle. It is not only the head turn but also the sudden slap takes time to perfect.
The struggle for the head slap comes because of the lost of balance. Novices tend to lose control after the slap, not after the turn. They know they need to spot so they try to find the spot they need, but at the time when they are not used to turn, they cannot maintain their alignment during and after the turn. To practice spotting, using a post-it sticker or putting an actual object right in front is useful. To keep control during and after the turn with extremely, practicing the slap with a half turn then progress to a 3/4 turn and finally reach the full turn, make sure you practice the turn with slow motion plus a sharp and clear slap. It helps articulate the tiniest detail during the turn. At first, you may find that the head weight seems to keep missing its proper place. It may take several months before you can keep the head weight not shifting after motion.
One thing that I feel worth to concern is that, tons of practice may not necessarily perfect your turning technique. There was a lady who kept practicing hard every day but still could get it right. It is not because she is not hard enough, but because she practiced it wrongly. Therefore, keen dancers, don't waste time on the wrong practice.
* Turning and Spotting part 1
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