Tessa Packard knows a thing or two about parties. Whether throwing a soirée in her beautifully curated studio in Chelsea or commanding festivities at 5 Hertford Street (her favourite haunt), the British fine jewellery designer is both an attentive host and sparkling guest.

Her playfully titled Under the Influence collection is inspired by the key to any good party – a well-shaken cocktail. “My favourite aesthetic has always been one that fuses timeless elegance together with vivid colour, a sense of wonderment and storytelling and a healthy dose of whimsy,” she says. “From conception to creation, cocktails embody these qualities in spades.”

The exuberant collection spans Highball Earrings, with hanging fruit slices in vivid dyed jade; a shimmering one-of-a-kind Campari necklace, strung with amethyst, pink quartz and garnet; and a gleaming Banana Bender charm in 18-carat solid gold. “I design jewellery for women who prioritise unique, clever design over carat weight; who wear pieces that express individuality and make other people smile.”

What is your favourite cocktail? When the sun is shining my alliances lie with the Brazilian Caipiroska. When the weather gets colder (especially at Christmas time) I switch to Whisky Sours.

Where is your favourite place in London for cocktails? Mark’s Bar at HIX.

What are the key components of a good party?

Getting the ratio right of people to space is crucial. Too much space and the party will fall on its face within an hour; too many people and you will be encouraging early departures. Guests must feel comfortable but the space crowded.

If you insist on playing music from the start, make sure there is at least one room which is quiet and easy on the ears. You’ll be surprised how many people find loud music an annoyance at parties.

Mix up the ages. The best parties have an equal mix of younger and older generations.

What is your go-to party outfit? Flat shoes. The minute your feet start hurting you always start thinking of bed.

Who does your catering? For formal parties, Mustard Catering. For informal parties I chuck a whole bunch of mismatching things together that I know will line the stomach and still taste great at 2am.

What makes a good guest list? Generally speaking, with larger parties, it’s kind on your guests if everyone there knows at least one or two people; at smaller soirées you can afford to be much braver and invite a mix of guests that have never met before.

What’s your party trick? Eating a whole lemon without wincing. I can also clear a whole room in minutes when it is time to go to bed. I have no qualms about asking people to leave.

Worst party faux pas? Overstaying one’s welcome.

What’s on your playlist? SIA – Cheap ThrillsBastille – PompeiiFlo Rida – Right Round

Most memorable parties of all time? There was one on a deserted island in the Canadian Arctic under the Northern Lights; a handful in Africa and a lot at home.

Best advice for blasting the cobwebs the next day? Ibuprofen before bed; eight hours sleep; three Bloody Marys when you wake.

Where do you spend Christmas? At home in Scotland.

What will you be wearing on Christmas day?A novelty Christmas jumper and jeans.

Where will you be this New Year’s Eve? Most likely at home, in front of the TV with three snoring dachshunds and a bottle of red wine. I hate any form of a New Year’s party and would much rather go to bed at 10pm.