Olivia Culpo's "worst fashion fail" was wearing the wrong underwear with an outfit.

Olivia Culpo

Olivia Culpo

The 25-year-old model doesn't think it is ever a "bad thing" to wear the same garments again even if it is not on trend at the time, but she does think it is a "bad mistake" to don inappropriate lingerie with certain outfits, which she has confessed to doing and massively regrets.

The brunette beauty told PEOPLE: "My worst fashion fail was when I forgot to wear appropriate garments.

"So, I don't think it's ever a bad thing to wear a certain outfit that might not be fashionable anymore or it might not be to someone's particular taste, I think your fashion sense should be a reflection of who you are and there's no wrong fashion moment. But one time I forgot to wear the right bra and that was a bad mistake. Confession."

Meanwhile, Olivia - who is currently dating sportsman Danny Amendola - has revealed she cannot leave her house without two of her favourite beauty products; Charlotte Tilbury's Flawless Collection Powder and Nars concealer.

She said: "The one beauty produce I cannot leave my house without is my Charlotte Tilbury Flawless collection powder, or the Nars crème concealer in custard - the best. They are just must haves, everyone needs to have those two products."

And the 'The Other Woman' actress has revealed she also has three wardrobe essentials, which are a black and white bodysuit, as well as high waisted jeans, and she relies on those items because she thinks when they are worn together they work for any time and "every occasion".

She said: "The one wardrobe necessity I cannot live without is a black and white bodysuit, and a high waisted pair of jeans, with that outfit you can't go wrong. Works every time for every occasion."

But the style icon - who recently partnered with PrettyLittleThing on her own capsule collection - has revealed she would love nothing more than to raid actress Blake Lively or fashion designer and Spice Girl band member Victoria Beckham's wardrobes.

Speaking about her fashion muses, she said: "If I could raid any celebrity wardrobe it would be Blake lively or Victoria Beckham or both."