answered
Q: What's the best way to coach a young leg spin bowler to disguise their wrongun better?
A: I'd say get your obvious wrongun working well and turning then start swiveling your hand around and see what happens. A fast arm action helps disguise deliveries. The final flick of the fingers the 'other' way really helps so work on that in the backyard to strengthen the fingers. Bowl to a mate who bats ok and video some deliveries. You can also practice on your own with a tennis ball