The tree: Kally Ellis
Florist Kally Ellis of McQueens worked all night to create the Christmas "tree" adorning the art deco staircase at Claridge's in London. The shimmering magnolia twigs are five metres high and drip with wispy white fronds of lichen, together with jewelled baubles that resemble Fabergé eggs.
Twenty years ago, Ellis gave up a job in the City to take over an east London florist run by an aunt of the late fashion designer Alexander McQueen. Ellis kept the name, and was soon supplying floral haute couture to celebrities and royalty, and styling events in as far-flung spots as Hollywood and Japan.
Her advice this year is to go into the garden and the woods for your floral decorations. She is ditching red and green for ivory, white and mist grey, with metallic gleams of silver, copper, gold and jade. "Stay with a simple palette," she advises. Ellis lives in north London with her husband and two teenage children.
"London has surprisingly easy access to nature," she says. "Comb parks, woods or heaths for fallen twiggy branches — the larger the better."
Add long stems of ivy, gather fir cones and fallen leaves and let them dry out, then glam them up with a spray can of gold or silver. Just a touch, not a blanket all-over spray. Look for dramatic pieces of bark, and use soft, dampened, springy moss at the base of displays. "Experiment and have confidence. Invest in some lovely gold and silver baubles and place them in bowls or around your logs, or cupped in the moss."
Get the look
* White bouquets are chic yet simple. Fill bowls with masses of white roses. To stop wilting, cut stems at an acute angle under warm water. White chrysanthemums, carnations and lilies are cheaper; mix them with glossy green stems of holly. Change the water regularly. Add white-feathered birds for a surreal touch (from Sainsbury's or Paperchase).
* Flower stalls at New Covent Garden Flower Market (Nine Elms Lane, SW8) stay open until 11am. For a wealth of unusual display items, visit C Best.
* Buy metallic fantasy on a budget at Zara Home, with hand-painted frosted baubles in a box, for £9.99, and white feather birds. (zarahome.com).
* Exquisite baubles, hand-made in the ancient German glass-blowing town of Lauscha, are available, £18 for 12, from manufactum.co.uk (0800 0960938).
The lights: Paul Dart
Paul Dart from south London, who trained in theatre design, is truly this year's Mr London Lights, creating "The Twelve Days of Christmas" above Regent Street, and the lights for Carnaby Street, Piccadilly Arcade, Leicester Square, Brent Cross and more. "I wanted to tell a story," he said. Dart had a team of 250 making the decorations in his studio in Old Kent Road.
He used digital printing for the words of the carol and its illustrations. You too can use your printer, Dart suggests. "Print out family photos, or other artwork from the internet, and then glue around baubles, varnish, maybe add a little glitter, and hang with ribbon. Or make family portrait place mats."
And lighting tips? Dart has round-the-year garden lighting. "Think of your windows as picture frames. Let flexes follow the outlines of twigs and branches to create pretty silhouettes. Don't spread lights out thinly — better to mass them together in one area. "
Get the look
* Use low-voltage lights, designed and labelled for outdoor use, from a reputable supplier. Connect to a power supply inside the house using a waterproof extension cable. You will, however, need to leave a window ajar — or hire a registered electrician to fit a weatherproof outdoor plug.
* Don't be mean with garden lights. A 10-metre string of 100 bulbs will light a bush or small tree (£40.99 from xmasdirect.co.uk, with strings that can be joined together). Simpler low-tech ideas include nightlights in jam jars hanging from trees.
The wow factor: Janet Wardley
Window displays in Harvey Nichols, Knightsbridge, are predictably offbeat, and have been designed for more than 15 years by Janet Wardley and her display team of 20. "We always start with fashion trends," she says. "This year we went oriental for a happy, uplifting and sparkly look. Be brave with colour at Christmas."
The windows are a riot of pink, purple, jade and yellow, with fans, feathers, butterflies, giant-petalled lotus flowers and chrysanthemums, plus glittering peacock tails. "Stick to a theme," advises Wardley. "Always keep in mind the colours in your room."
In her Victorian home in east London, where she lives with her partner and 12-year-old daughter, Wardley does a decorating hit on the whole house: "I'll even add a few bits to the kitchen."
But you don't have to buy everything new. "Try rearranging what you have already. Fill wine glasses and tumblers with baubles (some small, some large) group them together on a shelf, and spotlight if possible." Or you could fill a clear glass vase with snow-frosted fir cones, and mass candles in an empty fireplace.
Get the look
* Harvey Nichols make all their displays. At home, DIY decs could include huge paper flowers in neon brights, bows tied with wire-edged ribbon, strings of beads to scatter on surfaces. Find a treasure trove of display materials at trade suppliers DZD, lower-ground floor, 145 Tottenham Court Road, W1 (020 7388 7488; dzd.co.uk). Minimum spend £15.
* Browse the New Japan collection at John Lewis — it includes hanging kimono dolls for £4.50 each and cerise satin baubles at 75p (johnlewis.com).
* Visit orientalfans.co.uk for a vast variety.
* Feathers en masse are at thefeatherfactory.co.uk.
Portraits by Adrian Lourie