Lulu Kennedy, mentor to some of London’s most successful designers through Fashion East and founder of Lulu & Co, launched her debut collection for Marks & Spencer’s Indigo line last night.

Dressed in a white cotton mini skirt and faded sweater from the collection, she told us that she was asked to design the line after she’d appeared in the high street brand’s Leading Ladies campaign last year. ‘I couldn't believe it when they asked me to be in the campaign. I though they were ringing me to ask who I thought should be in it,’ she says. ‘And to have designed a collection for them – it doesn’t feel real. I’ll be going down to the M&S in Stratford Westfield on Thursday morning to look at it all.’

When she started work on the collection she bought in photos and fabrics picked up on her holidays in Tulum and Ibiza for inspiration but this isn’t just a holiday collection. The 19 pieces are designed to be versatile and work hard in your wardrobe whatever you may be doing throughout the summer months.

Kennedy’s favourite buys are the long white sundress, the boyfriend jeans and the sandals, but everything is already in rotation in her wardrobe. ‘I’m wearing it all but I didn’t want to just design it for me, it’s for everyone. Even my mum wants to wear half of it and that’s great,’ she says.

She was very hands on at every step of the design process and, after years working with fledgling labels, collaborating with such a hige brand was a revelation. ‘I’m so used to watching designers struggling with brilliant ideas that they can’t afford to execute,’ she says. ‘But the M&S team were so quick to make decisions and the resources were so great that I would say, “Wouldn’t it be great if we could do this,” and the next week there’d be samples for me to look at.’ In fact she enjoyed the process so much that she's already hard at work on a/w 2015 collection.

Lulu Kennedy for Marks & Spencer Indigo drops into stores and online on 14 May. Prices from £15 to £75.