There is a lot to be said for wearing something different. Standing by your principles is laudable in other arenas, but there is no virtue to be signalled by wearing navy, and in fashion, as in food, you miss half the fun if you refuse to try anything new. And the new new thing, is a yellow dress. It started almost a year ago, with Alicia Vikander’s strapless Louis Vuitton dress and Beyoncé’s (eponymous) Lemonade ruffles. Emma Stone wore one in La La Land and Natalie Portman to the Golden Globes. Emma Watson is incoming, in Beauty And The Beast.

I have no explanation for why the yellow dress is happening right now, beyond the fact that we are living in a time when the upset has become the new normal. Do not adjust your sets: the world is wearing yellow. Also, there is a hunger for good news. Optimism feels vital, and the sunny spirit of the yellow dress is the ultimate in dopamine dressing. The yellow dress is to the millennials of our uncertain times what red lipstick was to the women of the Blitz.

Because the yellow dress has been conjured out of the zeitgeist rather than copied from the catwalk, there are no rules as to how to wear it. Actually, that’s not quite true. I was trying a bit too hard to be super positive, there. There is a rule, and you’re not going to like it: no black tights. Yes, I know what month it is, but still. Don’t be a snowflake about this one, or you’ll end up looking like a bumblebee. Did you buy those just-over-the-knee boots I told you about a few weeks ago? Well, you should have, because that would solve the hosiery issue. Otherwise, I stand by my firmly held if not scientifically proven belief that if you put enough fake tan on your legs they don’t get cold.

There’s one more problem, though: yellow doesn’t suit you, does it? I knew you were thinking that, because everyone says yellow doesn’t suit them. But there are lots of yellows, from this one (Lucozade?) to lemongrass. The right one for you is out there. Believe.

• Jess wears dress, £130, topshop.com. Heels, £225, lkbennett.com. Chair, £85, habitat.co.uk.

Styling: Melanie Wilkinson. Hair and makeup: Laurence Close at Carol Hayes Management.