Shopping for a knock-out Christmas outfit, I felt listless, uninspired. Sometimes I draw up dresses in my mind and then try to find them in department stores.

What I really want is a dress that would make me feel I was hearing Cole Porter’s You’re the Top for the first time, a dress that could convince me I had composed it myself, in a mad fever, one warm spring night, or better still that the song had been written about me.

Vaguely, I imagine a wall that was upholstered in raspberry silk damask 150 years ago, then I subject it to a great deal of greyish London light, one or two spills, a scuff from an illegal indoor football match or a spurned suitor’s boot — the wonders it has seen it will never tell — and then I try to find a dress exactly that colour in a shop. It isn’t easy.

Or I might imagine a bit of raw-edged dark lace, the fronds sticking up like eyelashes, then attach it to a square neck, add a narrow-cut cotton sateen bodice and a few modest frills at the hem ... but, when I pop into the gowns department of a large store in the hope of seeing it languishing, quietly waiting for me, it’s never quite there.

Some days, the imaginary dress is chiffon with polka dots the size of aspirins, or even Solpadeines, with bracelet-length sleeves, or it is unlined tweed shot through with silver. It might be blackwatch silk tartan. At the moment, it is a pale rose gold colour with a scalloped neckline and hem. In the boutique in my head, they have all the sizes and it’s always sale time. “Madame, it could have been made for you,” the sales staff say, and other phrases like that. I don’t even really need to leave the house any more.

Shopping became even harder this spring when I watched a Pina Bausch dancer burst on to the stage in perhaps the most glamorous dress I have ever seen: A short, frothy, white confection made entirely from bubble bath foam. With that extraordinary garment — witty, fresh, charming and referencing the deep mysteries of the sea — almost nothing can compete.

I can’t get it out of my mind.

Of course, a bubble bath dress would ensure your appearance at any party would be briefish but, as it is always hard to know when best to leave, that could be a boon. I suspect such a garment would not provide much warmth for its wearer, but it would certainly provoke a great deal among the other guests. For full-wattage party glamour, it seems to me, the bubble bath dress cannot be beaten. I do hope it is a look that takes off.

I’ve always liked dresses that weren’t quite made from dress material, but rather chainmail, feathers, tinsel, buttons, sweeties and sweetie-wrappers, compressed Coca-Cola cans ...

Not that I have ventured into this territory myself — actually I have! I once sewed about a hundred roses on to a dark blue shift and walked out into the night. I was 19 and it was a fancy dress Christmas party thrown by the English department at the college where I was a student.

I felt like a heroine primed for adventure. Anything might happen. As I stitched the blooms, I thought of Isabel Archer’s incautious levels of belief in herself, and others, in The Portrait of a Lady. That young heroine sometimes causes in me a tremendous burst of faith, hope and charity and at other times I mind that she is foolish and self-obsessed and naive. We are all familiar with the feeling.

That night, I walked gingerly to the party, trying not to shed my blooms. My college was renowned for its fidelity to the Romantic period and this detail had not been lost on any of the students. It was one of those gatherings chiefly notable for the fact that everyone was in love with the wrong person. There was an epidemic of misplaced affections that year.

Back in the actual shops, I tried on a dress I have already tried three times this year. It was perfectly nice, but no more. Something new always brings with it the chance for a relaunch but, if you’ve better things at home, it is right to resist, I think.

At the door, I was hit by a gust of fresh Christmas tree scent and suddenly in my mind I was stitching blue-green noble pine branches on to black velvet, at the neckline, at the hem and on the sleeves. I wonder ...

— Financial Times