You give them refs but you also elaborate on details.
When I was designing the star gal in sig, I wanted to connect to her personality. She's quite bubbly and loves bright colors(just to main traits I worked with). I had a idea that since galaxies are colorful, why not apply that onto her? So I wanted lots of stars everywhere, that includes inside her hair, eyes, and her outfit. I thought that it'll be really cool to have a dress that illuminates a galaxy underneath it(I was thinking of magical girls). So think about what you want and just go with it!