The Fashion Star host and fiancé Eric Johnson welcomed a baby girl named Maxwell Drew earlier this month.
Rachel Ashwell of Rachel Ashwell Shabby Chic Couture designed the nursery for Simpson and revealed some of the star's requests in a new interview with People.
"Jessica is very pretty and feminine, but she didn't want this to be over-the-top frilly," Ashwell explained. "The words she used were 'gypsy' and 'bohemian', so we brought in lavenders and mauves with a bit of pink and aqua."
Ashwell went on to say that she enjoyed working with Simpson and Johnson as they had great ideas and were not at all demanding.
"They were probably the most un-neurotic people I've ever known. Jessica wanted [the nursery] to be cosy and cute, and she was very respectful of Eric, asking, 'Do you like this?' And he was nicely opinionated," she recalled.
"I found being around them very inspiring to think, 'Wow, [this is] a real collaborative vision'. I even wrote them a little note saying, 'It's been such a privilege to be part of making your home for you, because I know it's going to be a house of substance'."