WATCH: Katy Perry Was This Lucky Grammy Nominee’s Personal Stylist

Not only was Katy Perry on double duty Grammy night as a nominee and performer, but you can also add stylist to that impressively long list.

The pop princess of style was more than happy to share her red carpet dos and don’ts when it came to her BFF and songwriting partner in crime, Bonnie McKee.

“We talked about outfits and seating arrangements. And I just never want to get my hopes up too high because it’s anyone game,” a rainbow-haired McKee told CB! on Grammy night about her first nomination for the smash hit “Roar” for Best Song of the Year.

“I sent her [Perry] a bunch of pictures of all the different dresses I tried on and she’s like ‘oh my god, you tried on so many dresses!’ And she liked this one!”

So… 40 dresses later (yes, 40) that Perry sifted through and McKee tried on, she finally settled on a stunning Gustavo Cadile strapless gown to celebrate music’s biggest night.

“I wanted to do an evil mermaid look,” McKee said clutching a Rauwolf bag with her stiletto crystal-embellished “evil nails.”

“They’re very dangerous. I’m covered in tiny cuts all over my body.”

And that’s not all. McKee takes the whole “beauty is pain” saying to a whole new level.

“I did a juice fast for five days, but this morning I had a donut. I was like ‘It’s not going to make a difference,’” she laughed.

“I’m really excited to go to [Las] Vegas and eat lots of pasta after this.”

Check out more with Bonnie in the CB! video above.

And watch Katy Perry tell us about hitting a high note with her special Grammys gown in the Celebuzz video below.