If you want to be a successful entrepreneur, you need to be passionate, focused on the business’ core values, and have your own niche in today’s market, a leading U.K. entrepreneur tells CNBC’s “Pop Up Start Up”.

“You’ve got to have a niche when you come into this very, very, very competitive world,” Baroness Mone of Mayfair, British entrepreneur and founder of Ultimo, a lingerie brand.

Michelle Mone founded Ultimo back in 1996 – which she has now sold to MAS Holdings – and has since expanded elsewhere in the business world, while simultaneously acting as a guest speaker and offering her expertise to those in the business world.

As a mentor for this week’s “Pop Up Start Up” episode – which sees two entrepreneurs turn their fashion-based products into a reality – Mone said it was important that entrepreneurs make sure they stand out against their competitors.

“When I first started Ultimo, I invented the gel-filled bra which was very famous and then I invented 15 other inventions,” said Mone.

“And I said to the (contestants), you need to find something that is a niche, maybe some innovation, maybe invent something, an issue that there is in the lingerie world for women.”

“You’ve got to just tackle that and launch with that, because if you just do the same as everyone else, then you’ll never grow your business.”

When it comes to building a business, Mone added that it was important for entrepreneurs to act fearlessly and have a positive mental attitude, yet warned that if “you become complacent you’ll be finished. You’ve got to keep going and fight every single day.”

“It doesn’t matter where you’re from, it doesn’t matter what education you manage to get, it doesn’t matter if you’re from money or not. If you have that passion, determination and a can-do attitude you will succeed in business.”

Having worked in business over the past two decades, the fashion industry has developed immensely especially with the introduction of social media. While social media is great for promoting a product, it also makes businesses more susceptible to criticism.

Despite this, Mone said social media was a good thing for communication with customers, as it allows businesses to receive honest feedback and find ways to fix any potential issues.

“Businesses are like a massive jigsaw and imagine just this big picture, and break it down into many, many pieces of a jigsaw,” said Mone.

“Every single piece from distribution to shipping, to retail to in-store promotions, to photography to marketing, to PR to innovation – every single piece of that jigsaw has to be perfect.”

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