Donna Ida Thornton, denim addict and founder of the Donna Ida boutiques, has a new project. She’s teamed up with McArthurGlen, the brand behind some of your favourite designer outlets, just as it launches it first ever campaign entitled, aptly, ‘The Art of Denim’. She’ll be opening a pop-up store packed hull of the most desirable denim brands around, including her very own line, IDA.

Always on the hunt for an insider’s guide, we thought we’d take the opportunity to pick Donna’s brains about all things denim.

What is it about denim that you love?
Denim is our modern wardrobe; hardwearing, effortlessly cool and versatile. I love that it can be casual or smart with a quick change of heel or a different jacket.

What are the denim brands that you can't live without?
I wear a lot of J Brand. Its Leather Leggings are my a/w 2013 staples and their boyfriend jeans Aidan in Santiago are so soft they're perfect for the weekend. I wear a lot of jeans from my new IDA range as they're all high-waisted and I love the fit. I also wear Paige, Citizens of Humanity and Mother Denim as they have the most comfortable skinny jeans around.

What is a/w 2013's biggest denim trend?
Back to blue is the biggest trend - we've definitely shifted back to the core denim that we love. It’s a sign of the times that we're looking for investment pieces over fast fashion. Jeans always continue to evolve, so many denim brands now have leather, suede and cord in their offering. It’s the best of both worlds, a perfect fit in a luxurious fabrics.

Are there any brands that we haven't heard of that we should be looking out for?
Frame Denim. Relatively new but making a huge impact at Donna Ida; we reordered on the first day they hit the shopfloor. The washes are nicely worn and faded. Try Frame Denim De Jeanne Skinny Jeans in Columbia Road for the perfect mid-blue or Le Garcon Boyfriend for a relaxed boyfriend with cool turn-ups.

What's the key to finding the perfect fitting jeans?

Visit a denim specialist, have an open mind and try what the sales assistant suggests. Listen to advice. Every pair of jeans has around 2% stretch, so make sure they’re not too big. The waistband should be snug, if you can fit two fingers down the back that's good, a whole hand is not. If your jeans are near perfect, look at alterations. We offer to taper legs, alter leg lengths, add zips, remove pockets. We can even alter jeans to add elasticated maternity panels and then change them back after you've had your baby.

Who are your denim-wearing icons?
I'm inspired by lots of women past and present who all dress using the same common denominator - cool classic shapes, statement coats and jackets, killer evening wear. They all know what a waist is too. I look to Marilyn Monroe, Brigitte Bardot, Katherine Hepburn, Marianne Faithful, Anita Pallenberg and Kate Moss.

What do you wear when you're not wearing denim?
I wear denim everyday - but I do have a few standout evening dresses from Halston Heritage and L'Agence.

The Donna Ida pop-up boutique will open at Cheshire Oaks Designer Outlet on 5 October for a limited time only.

The ELLE team wears denim

Donna Ida's career tips