1. This class is all any Britney fan could ever want.
"Who here made up a Britney routine with their friends at school?" the instructor, Bonnie, asks. The entire class shoots up their hands.
Later on, during water breaks, we chat about the routines we made up in our bedrooms as teenagers. Fortunately, nobody asks to see my moves to "...Baby One More Time" B-side "Autumn Goodbye".
2. There is a lot of stretching.
We begin with 10 minutes of stretching to Britney deep cut "Outrageous". We're all excited to learn the routine to "Toxic". So much so that when the instructor plays it for the first time, there's whooping from the crowd.
3. The class is made up of all different levels.
There are regulars, who come to a class a week. ("I've been to the Beyoncé "Run the World" one, that's my favourite," one tells me.) And there are people who just drop in every so often, as well as newbies like me.
As you can see from the above photo, I am very much at the bottom of the class. But that's OK! Instructor Bonnie is really enthusiastic, and goes through each move as many times as is needed.
4. You will have extreme gym kit envy.
My class mates are decked out in custom trainers, with shirts tied around their waists. If you want to check out the styles, you can follow #SOSKitclub on Instagram.
5. We learn that Britney's choreographer, Brian Friedman, is basically a genius.
I mean, for example.
6. The routine takes its inspiration directly from the "Toxic" video.
Whether it's pretending to push the drinks trolley (above) or channelling catsuit-in-the-glass-box-Britney.
7. To dance like Britney, you have to become Britney.
"What's your name?" instructor Bonnie calls out. "Britney!" we answer eagerly.
"You are not in a gym in Clapham", she says. "You are on stage, opening night of the In the Zone tour. You are Britney!"
8. Make sure to grab your headset mic.
9. Tap your body whenever possible.
10. Shake up your hair.
11. And above all, use your arms.
12. When channelling Britney, "goddess arms" are the most important bit.
"Britney whips her hair a lot and her arms are never still", instructor Bonnie says. "She always commands the audience with her arms."
Goddess arms look a bit like ¯\_(ツ)_/¯.
13. Therefore a Britney walk must always include some kind of arm movement.
14. Don't forget to whip your hair too.
Instructor Bonnie explains how to whip your hair without hurting your neck:
Keep the move small. Place the emphasis on the first section of the move and let the momentum carry it round. Put your head to the side, and then and bring it around. Bend your knees too if you like.
As Britney demonstrates.
15. And when the routine is ready, strut your stuff.
Find classes in London and Manchester here.
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