Swimsuit shopping. Ugh.

Unless you are one of those ‘A Bikini A Day’ Instagram girls, trying on a new swimsuit is a nightmare for most women.

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Unless you look like this, swimsuit shopping is no fun. Photo: A Bikini A Day

Forget the forensic overhead fluorescents. What about the full-length mirrors that reflect your profile?

If you’re losing your jawline, have had children, or even dinner, you’ll know what I mean.

I’ve seen things in those wraparound mirrored bathrooms. Visions so terrible, they’ve made me check out of Crown Towers.

I’ve been wearing the same two swimsuits for several years now, just to avoid stripping off and watching my bosoms spill out the side of a new one. I refuse to go up a size. I don’t want to see the back of my arms.

So in a fit of pique (and maybe a slight hangover) I decided to shop for a swimsuit online instead. I clicked onto Net-a-Porter and began to scroll through the swimsuits, wondering what is like to be that woman who says, “Two small triangles on top and a tie at the side bottom will be perfect, I’ll take it in every colour!”.

She’s the same woman who can sit at the lunch table in her cossie and get creases in her stomach when she bends forward, not rolls.

“Anyway, I’m over all that body image angst,” the wildly oscillating voices in my head reminded me. I’ve truly given up caring whether I have a couple of extra kilos, or cellulite. That all feels very 90s to me.

But (and isn’t there always something?) I now worry about sun spots. My fair, Celtic skin means after any time in the sun whatsoever, and despite the lashings of SPF50, I come back looking like a slice of mortadella.

I think I lost the melanin in my driving arm somewhere in my thirties. Fake tan makes it looks worse, it grabs on the dark spots and slides over the white. I need pancake makeup.

Perhaps not entirely what Kirstie was looking for? Photo: Getty

So, when I spotted a black designer swimsuit with long sleeves and a zip to the throat, but with high-cut legs, I thought ‘bingo’.

It was a little Bond girl, a bit Dr No, sexy and practical. It said: “I’m covered up, but still sporty and fun-loving, I may be paddle boarding later, and I don’t care if my legs aren’t covered, it’s my cleavage I’m more worried about”.

Cleverly, the model in the photograph was headless, so I made the easy jump to believing that my body would look rather like hers once I was zipped into this wonder suit. I think I missed the fact that she was hired because of her thighs, or lack thereof, and that she was probably about 15.

Yes. Gee I was clever. This was the designer version of the neck-to-knee disasters that Tyra Banks and Nigella Lawson were unkindly snapped wearing by the paparazzi one summer in Sydney.

The voices in my head that ignore cold, hard reality told me I’d be sitting beside Bronte Pool all day in my new suit, wearing a baseball cap and aviators and white lipgloss, very Gilles Bensimon Elle magazine in the late 80s.

I may, or may not, strap a diving knife to my tanned thigh (for decorative purposes only). Buy. Confirm. Ship.

Three days later my package arrived. I don’t know what I had imagined the fabric was going to be, but I assumed it would be some lightweight futuristic techno material that would keep me cool and UV protected.

I ripped open the tissue and pulled out – a wetsuit. A thick, neoprene (nicely cut) wetsuit.

It just happened to be 38 degrees in Sydney that day. And I hadn’t worked out the English pounds conversion.

It was a $755 wetsuit that, once I zipped myself into it, made me look not unlike like a sweaty Danny De Vito as the Penguin in Batman.

I am very sure Elle MacPherson has never had these problems.