"Hur sjunger hon?"
Translation:How does she sing?
Does this means - how's her singing? Or literally, how does she sing? whereby the answer will be 'she sing by ...'
It means How's her singing? like did she sing good/bad
Not How does she produce musical sounds with her voice?
I'd honestly interpret it like the latter, "How does she produce musical sounds with her voice?" It could definitely mean either.
How should i phrase it if I want to say - how did she sing so nicely? Or how did he do it?
If one interprets "How did he do it" as "How did he succeed to do it", then it could be translated as "Hur lyckades han göra det?". Then you can translate "how did she sing so nicely" as "Hur lyckades hon sjunga så vackert/fint?"
Depending on your interpretation you can use verb "can - could": How did he do it? = How could he do it? -- Hur kunde han göra det? How did she sing so nicely? ----- Hur kunde hon sjunga så vackert/fint?
Or possibly a combination of both - kunde lyckas. How did he do it? = How could he succeed to do it? -- Hur kunde han lyckas göra det? How did she sing so vackert? = How could she succeed to sing so nicely? -- Hur kunde hon lyckas sjunga så vackert/fint?
Does it help? Do you want to express something else?