If you're at all interested in planet fashion you'll know that right now it's not so much the clothes as the accessories that count. And when it comes to accessories, jewellery is the star player this season. Add the right pieces to a work-a-day dress and it can be transformed into glad rags instantly. And whereas not so long ago if you wanted to buy jewellery you had to go to a pukka emporium, an antique shop or the glittery counters of the big department stores, these days you might do better to stalk the fashion floors. Ever since Marni turned some odd bits of fabric and plastic into the most sought-after necklace of the season a few years back, all the fashion boys and girls are at it.

At the top end of the market Burberry Prorsum has the most stunning glass necklace (not cheap, though, at a whisker under £1,000), Louis Vuitton has its own show-stopping, burnished-metal necklaces, and perhaps most fabulously of all Dries van Noten showed just what could be done by using fistfuls of bangles to make a necklace (in case you're interested, Liberty still has a few at £400 a time, and if that's too much there's nothing to stop you having a go yourself by stringing together a handful from Accessorize).

Meanwhile, on the high street, Topshop, H&M and French Connection have some surprisingly effective pieces. At Topshop there is a singularly cute filigree and tassel pendant for £20; or try H&M for crystal and “diamanté” chandelier earrings at £4.50. Since jewellery these days is designed entirely to be decorative and fun - swank and show are very vieux chapeau - it follows that anything made from plastic, glass, paper, shells, bone, wood or metal can be used, provided it is ornamental enough. One of my favourite necklaces, for instance, is made from old Venetian glass trading beads and cost only £35. Improvisation and ingenuity not only saves a small fortune (such as the price tag of the Burberry Prorsum necklace) but it means you get a one-off.

The other tactic, for those who don't fancy doing it themselves, is to go for vintage costume jewellery, which has the inestimable advantage of giving a lot of drama for your buck. John Lewis, on Oxford Street, in London, has a costume jewellery counter on the ground floor and I've lost count of the number of pieces I've admired on friends that turn out to have come from there. I have an eye-catching green and silver bracelet that cost about £40, and there's always a selection of brooches, bangles and necklaces, much of which is under £100. I have just found a black bear brooch with a diamanté cluster for £45 and a 1930s- style bone and gold link necklace for £55.

Felt, at 13 Cale Street, London SW3 (020-7349 8829), always has a wonderful selection of vintage costume items, all of which are clearly labelled. Its prices start at £30, though some vintage 18-carat gold earrings are £250. If you're feeling extravagant, Eliza Poklewski has some pieces by one of my favourite jewellers, Pippa Small, as well as a collection of Felt's own designs.You'll soon be able to browse the full range on its website, www.felt-london.com.

Debenhams has made a name for itself in recent years with its diffusion lines by famous designers such as John Rocha and Jasper Conran, and now it is doing the same for jewellery. Check out EB by Erickson Beamon (www.debenhams.com), which has lots of delicious-looking necklaces at prices that start at £20 (yes, really), while Angie Gooderham offers a gorgeous, huge brown cuff with a black rose for £50. Cuffs, you will have gathered, are very in vogue.

Finally, let me direct you to www.net-a-porter.com, where there's as good a selection of the current looks as can be found anywhere. You could get Marni's cult necklace - ribbon-strung chunks of turquoise with two black and terracotta central stones, as seen on the runway - for £335. Kara Ross's boutique collection is well-priced: a large, floral anaconda cuff costs £270. Monica Vinader and Erickson Beamon both have some gorgeous rings - the latter has more intricate designs, while Vinader goes in for single whopping stones. Prices start at about £100.

Just remember that this season it doesn't have to be real - Mlle Chanel would have so approved.

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