And as David E. Barton says, there are lots of free pleasures which we forget because we're so busy spending money, like parks and museums and the simple joy of a country walk.

It's all so easy and straightforward. And the best thing is, you have to start out by going shopping! The book says you should begin itemizing every single purchase in a single normal spending day and plot it on a graph. It stresses that you should be honest and not suddenly curtail or alter your spending pattern – which is lucky, because it's Suze's birthday on Thursday and I've got to get her a present.

So on Monday morning, I stop off at Lucio's on the way into work and buy an extra large cappuccino and a chocolate muffin, just like I usually do. I have to admit I feel a bit sorrowful as I hand over my money, because this is my last ever cappuccino and my last ever chocolate muffin. My new frugality starts tomorrow – and cappuccinos aren't allowed. David E. Barton says if you have a coffee habit you should make it at home and take it into the office in a flask, and if you like eating snacks you should buy cheap cakes from the supermarket. 'The coffee merchants are fleecing you for what is little more than hot water and polystyrene,' he points out and I suppose he's right.

But I will miss my morning cappuccino. Still. I've promised myself I'll follow the rules of the book – and I will.

As I come out of the coffee shop, clutching my last ever cup, I realize I don't actually have a flask for coffee. But that's OK, I'll buy one. There are some lovely sleek chrome ones in Habitat. Flasks are actually quite trendy these days. I think Alessi might even do one. Wouldn't that be cool? Drinking coffee out of an Alessi flask. Much cooler than a takeaway cappuccino.

So I'm feeling quite happy as I walk along the street. When I get to Smith's I pop in and stock up on a few magazines to keep me going – and I also buy a sweet little silver notebook and pen to write down everything I spend. I'm going to be really rigorous about this, because David E. Barton says the very act of noting down purchases should have a curtailing effect. So when I get into work, I start my list.

Cappuccino – ?1.50

Muffin – ? 1.00

Notebook – ?3.99

Pen – ? 1.20


Magazines – ? 6.40

Which makes a grand total so far of… ?14.09.

Gosh. I suppose that's quite a lot, bearing in mind it's only 9.40 in the morning.

But the notebook and pen don't count, do they? They're like course requirements. I mean, how on earth are you supposed to note down all your purchases without a notebook and pen? So I subtract both of those, and now my total comes to… ?8.90. Which is much better.

Anyway, I'm at work now. I probably won't spend anything else all day.

Oh God, though. Somehow, spending nothing is absolutely impossible. First of all, Guy from Accounts comes round with yet another leaving present to give to. Then I have to go out and get some lunch. I'm very restrained with my sandwich – I choose egg and cress, which is the cheapest one at Boots, and I don't even like egg and cress.

David E. Barton says that when you make a real effort, particularly in the early stages, you should reward yourself, so I pick up some coconut bath oil from the Natural range as a little treat. Then I notice there are double Advantage points on the moisturizer I use.

I love Advantage points. Aren't they a wonderful invention? If you spend enough, you can get really good prizes, like a beauty day at a hotel. Last Christmas I was really canny – I let my points build up until I'd accumulated enough to buy my granny's Christmas present. What happened in fact was, I'd already built up 1653 points – and I needed 1800 to buy her a heated roller set. So I bought myself a great big bottle of Samsara perfume, and that gave me 150 extra points on my card – and then I got the heated roller set absolutely free! The only thing is, I don't much like Samsara perfume – but I didn't realize that until I got home. Still, never mind.

The clever way to use Advantage points – as with all special offers – is to spot the opportunity and use it, because it may not come your way again. So I grab three pots of moisturizer and buy them. Double Advantage points! I mean, it's just free money, isn't it?

Then I have to get Suze's birthday present. I've already bought her a set of aromatherapy oils – but the other day I saw this gorgeous pink angora cardigan in Benetton, and I know she'd love it. I can always take the aromatherapy oils back or give them to someone for Christmas.

So I go into Benetton, and pick up the pink cardigan.

I'm about to pay… when I notice they've got it in grey as well. The most perfect, soft, dove-grey angora cardigan, with little pearly buttons.

Oh God. You see, the thing is, I've been looking for a nice grey cardigan for ages. Honestly, I have. You can ask Suze, my mum, anybody. And the other thing is, I'm not actually on my new frugal regime yet, am I? I'm just monitoring myself.

David E. Barton says I should act as naturally as possible. So really, I ought t act on my natural impulses and buy it. It would be false not to. It would ruin the whole point.

And it only costs forty-five quid. And I can put it on VISA.

Look at it another way – what's forty-five quid in the grand scheme of things? I mean, it' nothing, is it?

So I buy it. The most perfect little cardigan in the world. People will call me the Girl in the Grey Cardigan. I'll be able to live in it. Really, it's an investment.

After lunch, I have to go and visit Image Store to choose a front cover picture for the next issue. This is my absolute favourite job – I can't understand why Philip always offloads it onto someone else. It basically means you get to go and sit drinking coffee all afternoon, looking at rows and rows of transparencies.

Because, of course, we don't have the editorial budget to create our own front covers. God no. When I first started out in journalism, I thought I'd be able to go to shoots, and meet models, and have a really glamorous time. But we don't even have a cameraman.

All our sorts of magazines use picture libraries like Image Store, and the same images tend to go round and round. There's a picture of a roaring tiger that's been on at least three personal finance covers in the last year. Still, the readers don't mind, do they?

They're not exactly buying the magazines to look at Kate Moss.

The good thing is that Elly's editor doesn't like choosing front covers either – and they use Image Store, too. So we always try to work it that we'll go together and have a good matter over the pics. Even better, Image Store is all the way over in Notting Hill Gate, so you can legitimately take ages getting there and back. Usually I don't bother going back to the office.

Really, it's the perfect way to spend an afternoon. (A paid afternoon, that is. Obviously, I'd be thinking a bit differently if this was a Saturday.)

I get there before Elly and mutter 'Becky Bloomwood from Successful Saving', to the girl at reception, wishing I could say 'Becky Bloomwood from Vogue' or 'Becky Bloomwood from Wall Street Journal'. Then I sit on a squashy black leather chair, flicking through a catalogue of pictures of glossy happy families, until one of the trendy young men who works there comes and leads me to my own illuminated table.

'I'm Paul,' he says, 'and I'll be looking after you today. Do you know what you're looking for?'

'Well…' I say, and importantly pull out my notebook. We had a meeting about the cover yesterday, and eventually decided on Portfolio Management: getting the right balance. Before your head falls off with boredom, let me just point out that last month, the coverline was Deposit accounts: put to the test. Why can't we just once put self-tanning creams to the test instead? Oh well.

'I'm looking for pictures of scales,' I say, reading off my list. 'Or tightropes, unicycles…'

'Balancing images,' says Paul. 'No problem. Would you like a coffee?'

'Yes please,' I beam, and relax back in my chair. You see what I mean? It's so nice here. And I'm being paid to sit in this chair, doing nothing at all.

A few moments later, Elly appears with Paul, and I look at her in surprise. She's looking really smart, in an aubergine-coloured suit and high heels.

'So it's swimmers, boats, and European images,' says Paul to her.

'That's it,' says Elly, and sinks into the chair beside me.

'Let me guess' I say. 'Something about floating currencies.'

'Very good,' says Elly. 'Actually, it's "Europe – sink or swim?"' She says it in an incredibly dramatic voice, and Paul and I both start giggling. When he's walked away, I look her up and down.

'So how come you're so smart'

'I always look smart,' she parries. 'You know that.'

Paul's already wheeling trolley-loads of transparencies towards us and she looks over at them. 'Are these yours or mine?'

She's avoiding the subject. What's going on?

'Have you got an interview?' I say, in a sudden flash of genius. She looks at me, flushes, then pulls a sheet of transparencies out of the trolley.

'Circus acts,' she says. 'People juggling. Is that what you wanted?'

'Elly! Have you got an interview? Tell me!'

There's silence for a while. Elly stares down at the sheet, then looks up.

'Yes,' she says and bites her lip. 'But-'

'That's fantastic!' I exclaim, and a couple of smooth looking girls in the corner look up. 'Who for?' I say more quietly. 'It's not Cosmo, is it?'

We're interrupted by Paul who comes over with a coffee and puts it in front of Elly. 'Swimmers coming up,' he says, then grins and walks off.

'Who's it for?' I repeat. Elly applies for so many jobs, I lose track.

'It's Wetherby's,' she says, and a pink flush creeps over her face.

'Wetherby's Investments?' She gives a slight nod, and I frown in bemusement. Why is she applying to Wetherby's Investments? 'Have they got an in-house magazine or something?'

'I'm not applying to be a journalist,' she says in a low voice. 'I'm applying to be a fund manager.'

'What?' I say, appalled.

I know friends should be supportive of each other's life decisions and all that. But I'm sorry, a fund manager?

'I probably won't even get it,' she says, and looks away. 'It's no big deal.'

'But…'

I'm speechless. How can Elly even be thinking of becoming a fund manager? Fund managers aren't real people. They're the characters we laugh at on press trips.

'It's just an idea,' she says defensively. 'Maybe I just want to show Carol I can do something else. You know?'

'So it's like… a bargaining tool?' I hazard.

'Yes,' she says, and gives a little shrug. 'That's it. A bargaining tool.'

But she doesn't sound exactly convinced, and she's not nearly as chatty as usual during the rest of the afternoon. What's happened to her? I'm still puzzling over it as I make my way home from Image Store. I walk down to High Street Kensington, cross over the road and hesitate in front of Marks and Spencer.

The tube is to my right. The shops are to my left.

I must ignore the shops. I must practise frugality, go straight home and plot my expenditure graph. If I need entertainment, I can watch some nice free television and perhaps make some inexpensive, nutritious soup.

But there's nothing good on tonight, at least not until EastEnders. And I don't feel like soup. I really feel as if I need something to cheer me up. And besides – my mind's working fast – I'll be giving it all up tomorrow, won't I? It's like the beginning of Lent. This is my Shopping Pancake Day. I need to cram it all in before the fast begins.

With a surge of excitement I hurry towards the Barkers Centre. I won't go mad, I promise myself. Just one little treat to see me through. I've already got my cardigan – so not clothes… and I bought some new kitten heels the other day – so not that… although there are some nice Prada type shoes in Hobbs…

Hmmm. I'm no sure.

I arrive at the cosmetics department of Barkers and suddenly I know. Makeup! That's what I need. A new mascara, and maybe a new lipstick. Happily, I start to wander around the bright, heady room, dodging sprays of perfume and painting lipsticks onto the back of my hand. I want a really pale lipstick, I decide. Sort of nudey beige/pink, and a lip-liner to go with it…

At the Clarins counter, my attention is grabbed by a big promotional sign.