The fashion maven, who dresses Thandie Newton, Sarah Jessica Parker and Maggie Gyllenhaal in addition to Brie, stopped by the ET studios to give us the scoop on red carpet styling.
Walsh chose a stunning strapless black column gown with giant wing-like bedazzled bow for the GLOW actress, who was nominated for Outstanding Performance by a Female Actor in a Comedy Series. It was one of the standout looks from the silver carpet, and the stylist knew it was "the one" when she first laid eyes on it a month ago when Miu Miu sent two options to choose from.
"It's so funny. This happens very rarely that you find a dress early and it's just oddly perfect and all the stars line up that it works out," said Walsh.
Although Walsh usually avoids dressing her clients in black on the red carpet, this particular gown was undeniably show-stopping and instantly convinced her to break the rule.
"I wanted to do a cape forever. I'm such a girl. I love bows, giant bows, everything very feminine, but I also wanted something that felt incredibly fashion and incredibly streamlined and modern and chic. And it checked all those boxes and on her beautiful figure, it was just like heaven," gushed Walsh.
The stylist did admit it can get tricky with an oversized, voluminous element like the bow, which can look costume-y when not tailored properly. The bow was attached at the neck like a choker and strapped onto the back of the dress via hidden straps. Walsh made sure the dress underwent multiple alterations and she even had a tailor on-site the day of. This proved to be very helpful when the zipper broke.
"It's the weirdest thing in fashion. You can have the most couture gown in the world and a zipper will break. It has nothing to do with the construction or the design or what have you. It just happens," the stylist explained.
So what's it really like to get ready with a Hollywood actress on one of her biggest nights? Walsh described that stylists usually get only a few minutes to dress the star after hair and makeup. But as long as she has completed all the preparations, such as doing fittings and choosing jewelry in advance, she's ready to go.
"It was very calm, lovely, lots of wonderful conversation. Just a little bit of hanging out before they get to go be Cinderella and I go home."
Besides Brie, Walsh shared her favorites from the night, which included Yara Shahidi, Margot Robbie, Rachel Weisz and Timothee Chalamet, whom she revealed does his own styling!