Lily James creates a scent for each character she plays.

The 36-year-old actress said her unique ritual makes her focus.

Lily told the new issue of Britain's HELLO! magazine: "Every day, when I'm getting ready, I spray whatever it is on, and suddenly it takes you to a place and focuses you.

"Scent is so seductive. I like to either spray scents that are already made, or I'll create one and put it together."

The star plays Whitney Wolfe Herd - the founder and CEO of the dating app Bumble - in the entrepreneur's biopic Swiped, and Lily said there is added pressure in playing a real-life person compared to a fictional character.

Lily explained: "With a real person, first and foremost, you want to do them justice.

"Feeling as though you could ever possibly have the right to tell someone's story is such a confusing conversation and something I think about a lot."

Even though she did not meet Whitney, 36, before working on Swiped - which tells the story of the businesswoman's life and her rise to become the world's youngest billionaire - Lily researched as much as she could about Whitney to do the role justice.

She admitted: "I watched hours of interviews with her, I read about her, I studied anything I could to get to know her.

"What I found was a life force and energy that is truly infectious."

And Lily - who recently admitted she felt "guilty" and a "bit of a fake" by starring in Swiped because she has never used a dating app - felt it was important to tell Whitney's story.

She explained: "I think because hers is a true story of triumph and of building a legacy.

"There have been a lot of films about male founders of big businesses, but not so many about females.

"Whitney is an inspiration, and her story is so powerful and full of hope and courage."

However, Whitney recently revealed that she tried to "shut down" Swiped because she did not want her life story told on the big screen.

In September, she explained to CNBC: "So, I can't make it through the whole trailer, it's too weird for me.

"No, I'm not involved in it. Frankly, I was informed about this movie after it was already off to the races.

"I think they had already written the script and done all these things. I even was asking my lawyer two years ago, like, 'What do I do? I don't want a movie about me. Shut it down!'"

However, Whitney's lawyer had bad news for the businesswoman.

She recalled her lawyer saying: "'There's nothing you can do, you're somewhat of a public figure, there's public information out there, they're going to do what they're going to do.'"

At the time of Whitney's interview with CNBC, she felt both "terrified" and "slightly flattered" about Swiped, and the entrepreneur did not know if she would watch it.

The Bumble founder - who is "honored" that the film's producers cast Lily to play her - added: "I don't know if I'm going to watch it or not.

"I'm, obviously, both terrified and maybe slightly flattered, but I think the strangeness and the fear of it outweighs any flattery.

"So, listen, we'll just see. I guess I've got to get some popcorn and stay tuned."