So, in a couple of days' time, it's bye-bye to my 20s. Adios. Ciao. That's it. Game over. May as well roll over and play dead, or at least play really wrinkled, which, if you listen to some beauty experts, is pretty much the same thing.

The cosmetics industry's obsession with eternal youth drives me crazy. You can't hold back time. That's the point: it's time, it passes, get over it. Remember all that agonising over your first spot/period/ bra? Well, was it really worth the effort? I find the anti-wrinkle industry sinister and misogynistic, but that doesn't mean I don't care about how my skin changes with age, and how best to look after it as it does so.

"As you move out of your 20s and into your 30s, you need to keep the circulation from becoming sluggish. Remember regularly to exfoliate face and body to keep the blood pumping," advises the lovely (and still glowing) Ruby Hammer, of Ruby & Millie. "As I have got older, I have noticed some differences in my skin's tone and texture. The area around my mouth has become slightly darkened and discoloured, which could be caused by sun damage, being on the pill a while, or a combination of the two," she adds.

This is particularly common with dark skin, but I hope I don't need to tell you not to touch skin-lightening creams with a bargepole. Instead, just buy a base (powder or foundation) that matches each shade of your skin, and blend the areas together. Wearing an SPF, investing in a good eye cream and ensuring you "have a top-notch concealer to hide a multitude of sins" are Ruby's other tips.

"Perfectly purified, regularly, properly, gently but deeply exfoliated skin with sunscreen of SPF 15 or above applied every day," says Lee Bradley of Philosophy when I ask how I should look after my skin now that it's a grown-up. And then adds, "Lots of water, lots of omega 3 and 6 oils. And take supplements if you can't stomach two to three kilos of herring or salmon a week."