Here’s some advice for anyone who has hired an architect, interior designer or decorator, and wants to talk to them in the next few days: don’t call their office, they won’t be in. They will be at one of the plethora of design shows on in Britain, some of which are part of the London Design Festival, which runs for ten days until September 25.

Anyone planning to overhaul their home should also be going, as the festival is Europe’s biggest interiors event: a showcase for the best styling and the latest technology, with something for every pocket and any taste.

But which to visit? That depends on what changes you want to make. Our seven-page guide talks you through the hottest trends for every room in the house, and where to find them. To get the inside track on colours, flooring and fabrics, go to Decorex or 100% Design. High-end designers, architects and furniture-makers – among them the interior designer Kelly Hoppen, the furniture brand Andrew Martin, Blenheim Carpets and Chesney’s, the fire-surround company – and bespoke brands all show at Decorex. Prices will probably be steeper, and the overall tone more conservative, than at exhibitions such as 100% Design, ReDesign, or Tent London, which showcase more cutting-edge work – think the furniture designer Tom Dixon, the wallpaper company Cole & Son, and Ercol, the funky retro furniture-maker. Don’t miss the satellite shows: 100% Design has several, including 100% Detail, which has a concentration of sustainable materials, as does Eureka, part of the ReDesign workshops. Products there are all in production; offerings elsewhere may still be prototypes. For fabric, head to Focus, where you’ll see collections from the likes of Zoffany and Jane Churchill.

Not all shows are open to the public every day, but they all have at least one day that is, usually at the weekend. They are vast, inspiring and make a great day out, even if you don’t buy anything. Try to visit several, so any decision about significant changes is an informed one. Where else can you find the best design that Britain has to offer, all under one roof?

Regardless of which show you visit, remember that great design is timeless, as Martin Waller, director of Andrew Martin, points out when asked which designer he rates the most. In his eyes, it’s the anonymous artisans behind China’s terracotta army, on display at the British Museum: “What unbelievable skill – to make a product that still inspires 2,000 years later.”

THE BEDROOM

Lately, bedroom fashion has been all about the linen, not the bed itself. That’s changing, as the enthusiasm for statement pieces and reinterpretations of antiques gains momentum. A great example is the four-poster: a sizeable bit of kit that, until now, has been impractical in many of the nation’s sleeping quarters. Now it’s been scaled down and reworked. In many cases, the canopy has gone, but the wooden posts, with intricate carving and turning, can be works of art in themselves, with the detail sometimes emerging through a layer of limewash. Lines are clean and simple, so keep the linen in the same spirit and ditch the overstuffed bolsters and fake-fur throws you bought a few seasons ago. That’s one of the great things about the bedroom – it is the simplest room in the house to update as you can easily change the look with accessories.

The baroque is still big, but the boudoir effect is passé. Instead, try tone-on-tone layers of linen, in neutrals such as stone and smoky grey. And opt for raw linens to be really ecofriendly. If you want a splash of colour, don’t go for a block. Even Designers Guild, famed for its rich shades, has lightened up: its new Flores range of bed linen still features bursts of hot pink and teal, but only as an accent. Strong colour has moved to the walls, where you shouldn’t be afraid to go bold – what you’re trying to do is create a cosy nest.

Sally Bendelow, head of Home at Marks & Spencer, says shades of purple, from amethyst to plum, are hot, and texture is a strong theme.

“Think shiny chrome or mirrored furniture, smooth velvet, silk, cashmere, crystals, matt woods, ceramics, even leather – and don’t forget conventional jacquards,” she says. However, she warns against going overboard – the idea is a look of pared-down opulence.

The fitted wardrobe is back, but make sure it is professionally fitted. Everything, from the television to jewellery cases, can go inside. Then feed your inner diva with a truly divine dressing table.

Shows to visit: Decorex, the Chelsea Antiques Fair; greatbighomeandfurniturestore.com

THE LIVING ROOM

Oversized is this season’s hot trend, following the lead of the Belgian Marcel Wanders. Lights, furniture, rugs, patterns – you name it, it’s big. And, at last, the square, boxy sofa in neutral fabrics is dead: long live colour. Adopt the theory behind statement pieces, and make sure the colours you use on your walls, upholstery and flooring complement each other – which even traditionally “clashing” colours can do. Try teaming purple and orange, for instance, or blue and green: it can work.

The look is all about juxtaposition, says Sandra Drechsler, creative director of Taylor Howes, the London-based interior-design studio. “Modern classics such as the Eames chair and Saarinen Tulip table are back in fashion,” she explains. “And look out for Jonathan Adler, an American interior designer and furniture-maker. His retro-inspired style is on target for next season and is refreshingly playful.”

Gold, new metallic and pearlised finishes show no sign of fading away, and it’s the finish itself, not the metal of the object, that’s important. If all this sounds a step too far, you’ll be relieved to know that plain black and white is also back in vogue. Carrara marble is the flooring of choice for high-end design clients. If you can’t run to that, try limestone or some of the synthetic coverings that mimic the effect – though nothing beats the real thing.

Shows to visit:100% Design, Tent London, Focus, Decorex

THE KITCHEN

The best tip for anyone investing in a new kitchen is this: do not, whatever you do, go for a highly fashionable or seasonal colour. This advice comes from someone who knows: Daniel Prozeller, sales director of Schiffini, the Italian manufacturer that developed the modular-kitchen concept in the 1940s. “A kitchen is a serious investment, and you want it to look good for many years to come, winter or summer,” he says. High-gloss turquoise was huge a few years ago, just as black is now. If you do want a strong colour, however, pick one you love and know you can live with for years.

Otherwise, go neutral. This doesn’t mean just white or beige – there are lots of other neutral shades, such as parchment. If you must have the colour du jour, use it on the walls (you can always repaint later) or in accessories as opposed to. If you can’t change it quickly and cheaply, don’t use it.

So, what will look up to the minute and stay looking good for years to come? For Prozeller, aluminium is the answer. It looks softer and warmer than stainless steel, it is lighter, cheaper and easier to use, and it is available in anodised black and silver. Combine it with lacquer and wood for a more eclectic look, and think about using exotic veneers for cabinets, worktops and floors: bamboo, for instance, is a popular, durable and ecofriendly material.

The combination of such “softer” metals and woods is a welcome change from the harsh edges of industrial-style kitchens – all angles and stainless steel.

In any utilitarian room, the trend is to try to create furniture that would also be perfectly at home in your living room. General lighting can be low-level, with cabinets “floated” slightly off the walls, to create a more open, airy appearance. Good lighting is crucial in working areas where knives, hot pots and pans are involved. Lighting can do more than just illuminate a workspace – it can create fabulous effects. If your budget can run to it, Prozeller suggests backlighting a solid sheet of naturally translucent onyx (£800 per metre, from Stone Age; 020 7384 9090, www.stone-age.co.uk). Those with more dash than cash can employ the same effect behind a glass splashback. Seeking inspiration? Smaller firms and individual designers often produce exciting one-offs.

Shows to visit:100% Design, Tent London, ReDesign

THE BATHROOM

Sepia-brown or royal-blue bathroom, anyone? No thanks. Thankfully, we learnt our lesson about the folly of coloured bathrooms years ago – and let’s not even mention gold taps.

If you’re overhauling your bathroom, says Laurence Pidgeon, director of Alternative Plans, one of the UK’s leading bathroom and kitchen design studios, leave the avocado in the kitchen where it belongs. “The look,” he says, “is, wrongly perhaps, considered to be a kind of zen minimalism – how a Scandinavian architect might approach a Japanese bathroom.”

In plain English, what you are aiming for is purity, simplicity and cleanliness, so sanitaryware should be white, chrome or stainless steel. Natural finishes look fantastic – think limestone, matt marble, wood veneer, even coloured glass – and all these materials look great as trim or in cabinets. When designing the layout, remember to include furniture: it’s remarkable how much we need to store in a bathroom. For a softer look, go for a mouldable material such as Corian, which is more often found in kitchens. It has some even more adaptable relatives, such as Exmar and Crystal Plant, which give sanitaryware a soft, sensuous and lightweight feel. These materials also come in a range of subtle shades.

If you want to incorporate bolder colour, limit it to splashbacks of coloured glass mosaics or backpainted glass wall panels, which are increasingly replacing conventional ceramic tiles. You can also change them easily.

Bathrooms in the 1990s were temples to hedonism; in the Noughties, they have two roles. They must transform into virtual day spas for one – or two – but must also be somewhere to take a quick shower on a workday morning. Crucially, there should be continuity and flow between here and the rest of the house. Pidgeon is particularly keen on the work of Agape (www.agapedesign.it), Boffi (www.boffi. com), Flaminia (www.ceramicaflaminia.it), Dornbracht (www.dornbracht.com) and Bisazza (www.bisazza.it), all of which employ trendsetting designers and architects.

Shows to visit: Decorex, 100% Design – and don’t neglect the satellite shows at both

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