As the doyenne of glamorous special occasion wear, fashion designer Jenny Packham has dressed everyone from royalty to Hollywood A-listers, and even found time to make some eye-catching shirts for her brother, wildlife presenter Chris Packham, when he worked on The Really Wild Show.

The designer, 56, lives in London with her husband, Mathew, CEO of her eponymous company which has flagship stores and showrooms in London, Paris and New York, showcasing her ready-to-wear and bridalwear collections, which are available at eminent stores, including Harrods and Harvey Nichols.

So many stars have worn her luxurious designs, dripping with crystals and sequins – from her first red carpet A-lister Sandra Bullock to Angelina Jolie, Taylor Swift, Gigi Hadid, Kate Winslet and, most famously, the Duchess of Cambridge.

Packham shares her insider knowledge of dealing with the stars, and the pressure she faces to make the dresses work.

What’s it like dressing someone for a red carpet event?

“It’s quite a challenge. It takes years sometimes to dress someone and when you’ve done it, you’re just worried about what everyone’s going to say, not because of the criticism, but because you want them to be happy.

“The worst thing is, if a star is criticised after they’ve worn something, I just feel I’ve let them down.”

She reveals in her new book, How To Make A Dress, that she has never paid to place a dress, unlike other luxury design houses who pay to place their designs on the stars.

How carefully do you have to tread with A-listers?

“Sometimes, we’re lucky enough to work with them collaboratively, like with Kate Winslet.”

The actress visited Packham’s Mayfair studio in faded jeans and a khaki jacket just four days before she needed the dress to wear at the premiere of Titanic 3D (in 2012). Such dresses often take weeks or months to design and make. But Winslet was available for a fitting, which is rare among A-listers.

On the day before the event, Packham visited the hotel where Winslet was staying, with a toile they had made overnight, and nipped and tucked the dress while Winslet kept a watchful eye on her reflection in the mirror. The big day came and Packham arrived with the finished dress and her ‘fit kit’ – a box of pins, a needle, thread and spare beads. It worked. The relief was palpable.

“She just transformed. What was great was that, within four days, because she was around, we could work through the different stages.

“Sometimes you work with stars through their stylist, which creates a gap between you and them. The more successful they are, the more A-list they are, the easier the process has been, because they are so much more experienced and more knowledgeable about what they feel good in.”

Do you have favourite stars you’ve dressed?

“It’s when I personally like them as an actress. I really enjoyed The Queen’s Gambit with Anya Taylor-Joy. While I was going through some of my archive photos, I found that we’d dressed her a few years ago, which was really nice.

“I’m a huge Kate Winslet fan, and am thrilled to have dressed her quite a few times, and I absolutely adore Christina Hendricks.”

What’s your favourite dress you’ve designed for a star?

“There’s a few. The red Bond dress with the lace up the back we did for Caterina Murino (for Casino Royale) is one.

“From the minute the film went out, we got lots of men ringing up and ordering that dress. It went on for a long time. Luckily it was a dress that could fit quite a lot of women, because of the strapping at the back.

“Then there’s the black dress we made for Kate Winslet (for the Titanic 3D premiere).”

Do you get nervous meeting celebrities?

“Not meeting them, but I do get nervous about not doing a good job. If I’m doing a fitting, I’m nervous it’s not going to look right. I usually have a back-up.”

Are there any stars you’d like to dress that you haven’t?

“I’d love to dress Tilda Swinton – because I don’t think I’ve got a hope in hell! But I just love her style and I think she’s an amazing actress. And I’d love to dress Cate Blanchett.”

Do you design dresses for yourself?

“I’m the last person who would design for myself, apart from my own wedding dress, which is probably one of the most challenging things I’ve done. I was 50, I didn’t want a traditional white wedding dress, but I did treat myself (she wore a dove grey lace dress).

“The lace came from Austria and we interlocked the lace, so there were no seams on it at all. From a craftsmanship and fabric point of view, that’s what I got out of it.

“I love Dries Van Noten and I have lots of his pieces in my wardrobe. I love the prints and the fabrics and the colours.”

How To Make A Dress by Jenny Packham is published by Ebury Press, priced £22. Available now.