Shirley Schoonmaker slowly looks me up and down. “I’m going to be brutally honest,” she says. “Your shoulders are rounded, your knees are tight and your tummy’s sticking out.” It’s partly what I’m wearing, I protest, smoothing down my puffy black tulip skirt. Schoonmaker shakes her head. “Everyone always has an excuse.”

And so begins one of the most excruciating hours of my life. Perfect Poise and Presence, the class is called, “a one-hour intensive session revealing how to enter a room with grace, get noticed for the right reasons and avoid irritating habits”.

My friends laughed when they heard. I am a harbourer of more than a few irritating habits — and I’m hardly renowned for my grace or poise.

Nevertheless, I doll myself up as best I can and totter along to the rather regal headquarters of High Society Secrets in Marylebone, Central London.

The company, which was set up by Schoonmaker in 2007 and now has bases in New York, Shanghai and Beijing, as well as every leading city in Britain, offers “fast and modern finishing school classes” in what Vogue magazine referred to as the “art of sophistication”. Sophistication does not come cheap; the classes range in price from £175 for a one-hour session to more than £2,000 for a week-long retreat.

What they promise to teach you, however, is priceless: how to make confident conversation; how to influence people; how to find your own style; how to be elegant; and, ultimately, claims Schoonmaker, how to be successful. I was sure I could wing it.

Schoonmaker is determined that I don’t. She covers me in masking tape to highlight my “lines”; I have one shoulder higher than the other, she says, and my feet roll outwards. She videotapes me walking up and down the room and then picks apart, piece by piece, my artful slouch, so carefully crafted in the school corridors of yore.

The camera records me as I sit down and stand up and sit down again. We watch it back, in excruciating detail. “You’re taking up a lot of space,” Schoonmaker frowns. “And look at all those angles when you stand up.

“You also fidget too much with your hands — lots of short, fast movements. You look a bit crazy. Like a mouse. A mouse is very low-status.”

And there you have it; I am a low-status mouse. I am a disaster of monumental proportions. Life will give me nothing. Lions, on the other hand, are life’s winners. Unfortunately, being a lion is not easy. When I walk I must lead with something called the solar plexus, situated somewhere around the bottom of my bra. Above me, holding my head up and keeping my neck elongated, there must be a “golden thread” at all times.

Schoonmaker runs a stick between my arms and back to keep my shoulders down, and straight.

When I speak, I must keep my hand movements slow and graceful. And when I sit, I must stand at right angles to the front of the chair, twist my upper half, lower myself down and tuck one leg behind the other. It must be done slowly and with no accompanying “poosh” sound, even on the pooshiest of sofas. It hurts the thighs.

But never has the utterance “no pain, no gain” been so true. I perform again for the camera in the corner and this time I am confident, poised, elegant. I am not my old self; I am a lion. I do not totter home; I stride. I look forward to my promotion.

www.highsocietysecrets.com

Essential etiquette

Master “life’s essentials” of elegance, poise and confidence (£230, www. finishingacademy.co.uk ) Tips, tricks and catwalk confidence from ex-model Katie Froud (£130, www.themodelworkshop.co.uk ) Instant impact through voice projection and body language (£75 London, www.thecatapultclub.com ) Improve your social presence on a “perfectly polished personal development” course (£600, www.shinepersonal development.co.uk)

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