The New York-based socialite was thrilled when she received the prestigious handbag - which is favourite of Victoria Beckham - as she knew she had made it.
She said: "It's a cliche, but I remember when I got my first Hermes Birkin. It was such a pivotal moment - especially living in New York - to have received it. It was like joining a fashion clique and finally becoming one of the tribe. While I use it now occasionally, it always reminds me of how I've progressed stylistically and how cyclical fashion is."
The 24-year-old beauty - who has launched her own jewellery line with Roberta Freymann - is a huge accessories fan as she believes they are what make an outfit.
She told vogue.com: "I can't live without my YSL Tribute heels and my Ray-Ban Wayfarers. Everybody thinks it's the clothing that makes an outfit, but more often than not it's the accessories."
Olivia is very into her fashion and likes a variety of designers because they all bring something different.
She said: "There are so many, but several have impacted me directly or shown me how to think about fashion in different ways. Emerging brand Bensoni really captures my feminine and playful side, while Victoria Beckham's collection is elegant for cocktails or evening events. When Mr. Valentino was still designing he truly understood what makes a woman look beautiful. I feel that Rachel Roy and Matthew Williamson get that too with their proper and bohemian looks, respectively."
