Structured, ladylike and Mad Men-inspired fashion is set to take over Randwick this Saturday, TV personality Zoe Balbi says.

The 27-year old Sydney Spring Carnival fashion ambassador helped draw barriers for Saturday's Group One Epsom Handicap at Sydney's The Star on Wednesday.

Balbi told AAP there would be a smorgasbord of colour on show for Sydney's biggest day of the spring, with ladies set to pop up in bright oranges, yellows and tangerine reds.

"But the structure is where the big 'oomph' comes in...(there'll be) cinched waists, even shift-type pencil skirts," Balbi said.

"There's all these great TV shows out and the designers are taking a leap from them, with little gloves and box hats coupled with the dresses."

Balbi herself will be rocking a custom-made outfit by the same designer dressing her for her upcoming wedding to NRL superstar Benji Marshall in January.

But her outfit will be following the "ladylike" racing attire rules, she said.

"I'm so excited. I won't tell you too much about it, but it's to the knees, with a pencil-like skirt and a bit of lace."

In the feature race, Balbi will be putting her money on the Gai Waterhouse-trained gelding Fat Al who drew barrier six for the Epsom.

"Fat Al is definitely up there," she said.

"It just seems the Waterhouse family produces these horses that just don't lose - touch wood."