The Made In Chelsea star kept things casual while meeting fans at the event, but still managed to showcase her enviable flat-as-a-pancake stomach!
Lucy opted for black jeans with heaps of rips down the front, teamed with chunky boots and a super-long cardigan.
The stylista revealed her silver belly ring in a cropped white tee, finishing her look with sleek and smooth locks and glossy raspberry lips.
Gorgeous Lucy also worked her favourite winged liner look while flaunting natural brows, fluttery lashes and a flawless complexion. Jel!
Lucy was promoting her new book The Dating Game, in which she gives advice to girls on relationships, falling in love, break-ups and dealing with exes.
The starlet - who has previously dated co-stars Spencer Matthews, Jamie Laing and Andy Jordan - also discusses her own personal romantic experiences in the new book.
Meanwhile, the Chelsea gang have jetted to the Big Apple where they will be filming a spin-off series called Made In Chelsea: New York, which is set to air this summer.
While most of the clan hit the airport on Sunday (25 May), Lucy took a flight alone yesterday after her signing, ready to join her pals in Manhattan.
Taking to Instagram, the reality star wrote: "Nice little glass of bubbly before I fly away #loner #NYC"
We're sure there are tons of young gentlemen who would have loved to join you, Luce!
What do you think of Lucy's outfit? Let us know by commenting below as the best comment across the site each week wins £50!
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