flesh out
US /ˌfleʃ ˈaʊt/
UK /ˌfleʃ ˈaʊt/

1.
desarrollar, detallar, dar forma a
to add more details and information to something to make it more complete or substantial
:
•
We need to flesh out this idea before presenting it to the client.
Necesitamos desarrollar esta idea antes de presentarla al cliente.
•
The author took time to flesh out the characters in her novel.
La autora se tomó su tiempo para desarrollar los personajes de su novela.