Well, nawaki pretty much means cloud tree, so I'm not sure what you're asking. Do you mean tips on how to make a small bonsai style tree with the round cloud look? If so, you'd do it the same way you would on the larger garden tree, just on a smaller scale.

Nawaki is actually "garden tree"

I find the 'cloud style too artificial, and way too time consuming to maintain. None of the trees I have native here ever look anything like that naturally.

What I want is traditional bonsai informal styles in a tree with a 10-15 foot height.

I live in a climate that potted plants outside are at risk, and in ground plants, of course, are difficult to root prune.

Here's a niwaki type Picea pungens. I think they look great!
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Not sure if this is what you have in mind, but here is a nice Pinus sylvestris.
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