Actress Sienna Miller says she doesn't "put on a look" every day because she favours casual clothes when taking daughter Marlowe to school.

"I wish I could say I'm always styled out. I buy nice jeans and great jumpers, but that's sort of what I wear everyday because I'm a mother and I'm doing a school run and it's 7:30 in the morning. I'm not going to put on a look," Miller told eonline.com.

Despite regularly featuring on best-dressed lists, the "Burnt" actress says she isn't a fashion expert and doesn't often attend shows.

"I'm not really a seasoned fashion week person contrary to popular belief," she says.

The 34-year-old actress joked she is "in denial" watching runway shows.

"I'm in denial because the 20 year olds that can model wearing it is a different thing," she said.