She's best known for the BBC2 TV show Mary, Queen Of Shops, where she's revived flagging retail businesses, but Mary Portas wasn't always set for a career on the high street. In her youth, she had ambitions of being an actress and even gained a place at the Royal Academy of Dramatic Arts.

However, when that didn't work out, Portas switched to design, studying graphics and visual display at Watford School of Art. She saw the potential in retail, first working for John Lewis and then joining Harrods in 1982, where she dressed windows as a visual merchandiser. She moved on to Topshop at Oxford Circus, London, before joining Harvey Nichols in 1990. It was here that Portas really made a name for herself, transforming it from just another posh London store into a cutting-edge fashion destination.

Then in 1997 she established her own retail consultancy, Yellowdoor, whose clients today include Oasis, Louis Vuitton and Swarovski. As well as presenting Mary, Queen Of Shops, earlier this year she hosted a sister show, Mary, Queen Of Charity Shops, which saw her transforming the image of UK charity shops from being the poorer cousins of the high street into must-stop shops.

After more than 20 years in retail, Portas, 49, remains as passionate and enthusiastic about the industry as ever. "That's because the consumer is constantly changing," she says. "I just keep on learning, trying to get that brilliant experience for consumers. I love it."

Over that time, she says, the industry has changed a great deal. "The influence of luxury brands like Gucci, Fendi, Louis Vuitton in the late 1980s and 1990s created a completely different dynamic – a different way of selling, which is responsible for the proliferation of brands that we have today. That's why the roles within the industry have developed enormously. Fifteen years ago, marketing roles didn't exist at the level they do now."

To many people, retail is still seen as a secondary career but that's not how Portas sees it. "The level of jobs in buying, design, merchandising, branding and business planning mean it's an incredibly sexy industry to work in. In the next few years, people will learn that they can forge good careers and earn great dosh at the same time."

After all, retail takes around £280bn each year over the tills in the UK. "We have grown a market in this country and it is vital to the economy," she says. "We really enjoy shopping – it's our favourite pastime and we should be proud of the incredibly varied high street we have, compared to most countries."

It's an understatement to say she's very passionate about the UK retail market and it's with this in mind that Portas is lending her expertise to a series of retail masterclasses for independent stores in conjunction with Skillsmart Retail. The classes will be delivered exclusively through the National Skills Academy for Retail's skills shops, and will give a great insight into improving retail businesses. The masterclasses, which start next spring, include Portas's advice on essential elements, such as visual merchandising, marketing, buying, finance and store vision.

There are, she says, key basics that all retailers need to get right to succeed. "It's simple. Number one: get the product mix right, or people won't buy. Two: it's about a shopping 'experience'. Consumers want to spend time somewhere that says something about them and the way they live their lives. Finally, it's service and specialism. If you don't know your stuff, if you are not a top expert on your products, forget about it. People go to the Apple store because of their specialism, even though it might be easier to buy it over the internet. That's the future."

The internet, of course, has had a massive effect on the modern high street. "It's created a whole new way of selling and communicating, and it is more relevant to consumers today," she says. "But it is the businesses that link the two together that will be the big winners on the high street. It's brought about availability, accessibility and convenience."

The recession has seen several big losers on the high street, from Woolworths and Zavvi to MFI, but it's not all bad news, she says. "We're not doing too badly, actually. There has been a bit of a shake-up in the level of service, and improvements in the integration between internet and bricks-and-mortar retailing, but that is a good thing."

It's a freshening up, basically, which she says is key to staying current and connected to the shopper. "Retailers also need to visit rivals, see what others are doing and know what inspires you. Sometimes I talk to retailers and ask: 'Does that really rock your boat?' Stand outside the store, look at competitors, go on the internet and read the kinds of messages that are going out to consumers, and always ask how you can do things better."

Massively important to all of this is a trained workforce. "It's absolutely vital. We haven't seen it yet, but it is going to come through more, because the ones who do have that knowledge and that service level, who are switched on and passionate about what they are selling, are the ones making money."

But not everyone gets it right. "I went to get my daughter a pair of shoes in a fashion shoe shop. It was awful. At the counter, I said: 'Keep the box, save the trees.' The sales assistant said if we didn't take the box, we couldn't return the shoes, so we left. It really annoyed me.

"Look at Pret A Manger: it doesn't matter how busy they are, they always smile and are incredibly friendly and efficient, and it's down to training. If it works for them, with that amount of customers through the door every day, why can't some of these high-street fashion stores be the same?"

Interestingly, it's one of Portas's old work haunts that she thinks gets service spot on. "In terms of service, I think Harrods is probably second to none. I was in their food hall the other day, and their knowledge and training is fantastic. I also love Oddbins, which is making a comeback. Staff will now talk to you about the wine, and people are prepared to pay a premium for that advice."

High-quality advice is clearly something Mary Portas knows a lot about, and it's something that she'll doubtless be asked for by the retail industry for many years to come.

For more information on Mary Portas's retail masterclasses, go to