For anyone aged between 18 and 40 between 2004 and 2005 – yes, you – Jude Law's stint in the phone-hacking dock yesterday and the subsequent turning over of his and Sienna Miller's relationship will have felt like the glow of warm, golden sunshine remembered from childhood. Who can forget what a beautiful thing they were together? Who doesn't feel a close – nay, personal – tie to what happened between them? Granted, that might have been because of all the phone-hacking, but let's skate over that.

And it wasn't just their relationship that we invested in, it was a whole boho, Primrose Hill way of life: an existence woven from low-slung disc belts, shrunken waistcoats and tiered maxiskirts, supplemented with a pair of grey Topshop Baxter jeans in student loan-friendly homage to Mossy.

So allow us then this wander down memory lane, as we reconstruct your wardrobe from that magical time. If you're anything like us, seeing these pictures again will feel a little like riffling through a box of your own memories. As if you were right there with them, lurking just out of shot in a fur gilet and moccasins.

1. Accessories were key
The ultimate accessory, of course, was Jude himself. Look at them here. Isn't it just like they've fallen off the top of Mount Olympus and come to frolic with us mortals for while (in an airport lounge)? But if you didn't have the boyfriend with the shoot-to-kill cheekbones (or any boyfriend at all, in fact) you could still amp up your look to Sienna proportions in, say, a wide-brimmed hat of the variety last seen on Marianne Faithfull, the only other woman to be simultaneously adored and envied for being someone famous's girlfriend.

2. As was simplicity
Part of the reason my roommate and I were quite so obsessed with Sienna was because her look seemed so attainable – pretty little vests or basic T-shirts, worn with skinny jeans (I bought my first pair in 2004 and haven't looked back – fairly sure I'll become one of those old ladies who only wears things that were fashionable when she was 19), a flat sandal with a bit of interest (here, metallic but often decorated with shells too) and a trusty-looking leather bag. Wardrobe staples all, but transformed like bread and wine at the altar by the Portobello touch of Sienna MIller.

3. Indecision makes for a great aesthetic
Before we became so savvy about styling, these sorts of 'thrown together' looks (literally) were le dernier cri in fashion sense. Not for Sienna the pedestrian constraints of wearing a dress as only a dress. Plus, you get maximum use out of all those simple basics you invested in (see no. 2) by wearing them all together. Note also the cowboy boots. When I bought my pair, I told myself 'cowboy boots are the sort of thing that never go out of fashion'. How wrong I was.

4. You are a free spirit, remember. A Free Spirit
And there is no way you'll dress up fancy, not even for your own sister's wedding. We all remember this look. It says at once 'I couldn't give a fig for stuffy dress codes' and 'I'm so pretty, I could go to a wedding in a fright wig and still look great.' You tried something similarly nonchalant at a wedding that summer and have had to ensure all photographic evidence was destroyed because, while restrictive undies and boho don't necessarily mix, a wedding without spanx is like a prison without bars. But you sure loved your fringed waistcoat, dangly gong earrings and punched leather slingbacks that summer. You bought all of yours from New Look.

5. The world is your pastoral symphony
Yep, that's a polythene bag and some Starbucks in your hand but that doesn't mean you're aren't a child of nature. Free-flowing skirts, a white tank (another clever basic), and sun-kissed honey highlights recreated for the masses in great tigress stripes by every hairdresser in Rotherham establish a feel of modern romance - which links back perfectly to the incredibly beautiful boyfriend you have, the two of you revelling in a latterday Woodstockian sexy paradise. There are those cowboys boots again. They may never have come round again, but they got a good airing during 2004-2005. They were also from New Look.

6. Priorities
Of course it looked like Sienna MIller didn't really care about what she was wearing, even when she looked amazing on holiday. Of course she didn't care: she was on holiday with Jude Law. This is what Buddhists believe to be the highest and most transcendent stage of nirvana, when all earthly pleasures (well, all apart from *that* earthly pleasure) fall away. Hands up those who still experience a subtle frisson of shameful joy whenever their boyfriend accidentally dresses like this on holiday. All of us then.

7. A farewell to arms
Just like Kate Moss, Sienna Miller knew the benefit of a sleeveless extra layer – they don't weigh you down or even keep you warm, but they provide a crucial extra element with which to hammer home your fashion credentials. Here, Sienna shows the many possibilities of a waistcoat: nautical because whynot; rabbit fur gilet for winter (yours was acrylic); and denim, in which to drink a warm bottle of Corona on the Heath as the sun goes down and this Pete Docherty person strums on a guitar. What many people don't know is that Sienna was part of a science experiment over 2004-5 to try and discover once and for all why posh girls never get cold arms.

8. Beachwear not just for the beach
Swimsuits with long skirts, what boho devilry was this? It worked though. You tried it to your lectures once and no-one even realised there was an uncomfortable gusset scenario going on downstairs. The reason they were fooled? The enormous belt that disguised the join between fabric and lycra at your hips: you had one made of golden discs, another multi-stranded with fake ammo, and one that was as wide as a small paperback book. Your friend borrowed it whenever she could. But when you saw Sienna in this dress, in the copy of Heat you religiously bought to monitor her look, your heart practically broke with yearning. You were tired of mocking up your one-piece. You even went and looked in Hampstead Bazaar, to see if they'd done 'a version'. They hadn't.

9. The It-bag
You still sometimes dream about having to choose between a Mulberry Roxanne or a Chloé Paddington.

10. Early adopter Uggs
'I know, right? They're soooo comfortable, and they go with everything. Plus, they're really flattering on your legs because they make your feet look so big'*

*Everyone, to their best friend, in 2005

11. Haircut heartbreak (yours, not hers)
You'd had a fringe cut in. You'd gone to sleep in plaits every night for a year. You'd watched her go dark for Casanova and bitten your lip, fearful that she'd messed with the source of all her power. You might even have gone to see Casanova, but you probably didn't. Come the crop, the spell was broken. It presaged bad things. It didn't move in the summery breeze in the same way. In fact, you suddenly realised as you looked up at the grey sky, summer was over! It had been for almost a year! Your tiered maxiskirt was osmosing dirty puddles and your felt hat sagged in the rain. You thanked Sienna, you cried for her and for Jude. You still know that you owe her, for style inspiration, for justifying the purchase of those cowboy boots, and for creating that Venus-and-Adonis template into which you have tried to squash every relationship you've had ever since. You think about Sienna every time you're walking in the park wearing ankle boots.