How does it feel to open for one of the world’s biggest pop stars in front of a crowd of 90,000 people? Holly Humberstone has the answer. Or at least she will soon.

“It’s a strange mix of nerves and pure, pure thrill.”

The 24-year-old is supporting Taylor Swift at Wembley Stadium on Friday as the superstar returns to London for a second helping of her Eras tour.

“I feel like the coolest person on Earth,” Holly tells BBC Newsbeat.

It’s a “full circle” moment for the singer-songwriter from Grantham in Lincolnshire because one of her “first proper shows” was just next door at Wembley Arena in 2020.

Back then, she was opening for Lewis Capaldi after he spotted her on the BBC Introducing stage at Glastonbury the summer before.

Now, she’s got gigs supporting Olivia Rodrigo and Girl In Red under her belt – but there’s not much that can prepare you for performing to tens of thousands of people at a stadium show.

“I’m just kind of mentally preparing myself,” says Holly.

“I would’ve thought that it would have gotten less scary by now, but, no, not really.

“I’m just gonna go and enjoy myself and try not to think about how many people will be watching me.”

The Walls Are Way Too Thin and Scarlett singer was a breakout star of lockdown.

Since winning the Brit Awards’ Rising Star prize in 2021, she’s released her first album and headlined a European and North American tour.

She found out in June she’d be opening for Taylor but had to keep quiet about it until she was formally announced a couple of weeks ago.

“It’s been really, really hard – especially keeping it from a lot of my friends,” she says.

“Obviously we’re all Swifties and a lot of them have been like, ‘Are you going to go to a Taylor show?’

“And I’ve just been like, ‘I so badly want to tell you that I’m going to be supporting, but I just can’t.'”

Thursday marked the first show of Taylor’s second five-day run at Wembley – and also her first show since cancelling her appearances in Vienna.

Austrian security officials say a 19-year-old was planning to kill “a large crowd of people” in a suicide attack at the show, leaving organisers with “no choice” but to cancel all three scheduled performances.

While London police have said there’s nothing to indicate a specific threat to her Wembley shows, fans have been told they’re not allowed to “Tay-gate” – to gather outside the stadium – as a safety precaution.

“It’s really scary,” Holly says. “Gigs can be dangerous places.

“You do feel a huge responsibility for everybody that comes to your show.

“It must be really terrifying for Taylor to have to think about looking after so many people.”

Holly’s one of five artists Taylor’s invited to support her for one night only, joining Sofia Isella, Suki Waterhouse, Maisie Peters and Raye alongside Paramore who’ve supported multiple shows.

She’s inspired by Taylor’s dedication to working with emerging female talent.

“It feels like a really nice space to celebrate female artists and girl power,” she says.

“So many of my inspirations have played on the Eras tour stage, like Muna, Gracie [Abrams], Griff…

“There’s so many of my incredible peers that are playing and just to be a part of that group is such an honour.

“I just want to do it justice and play the best show that I can play.”

Even with all the success she’s had over the past few years, Holly says she still doubts herself.

“It’s super-easy to focus on all the stuff that I haven’t been able to achieve yet,” she says.

“So it feels super affirming and super encouraging to get any kind of recognition from somebody like Taylor, let alone her asking me to support the biggest show in the world.

“It just makes me feel really good about myself and my career that somebody like her would have any kind of belief in me.”

She tells Newsbeat she didn’t have a chance to speak to Taylor before the gig but hopes they’ll have a chance to connect.

“I don’t know what I’d have to say to her, apart from thank you,” Holly says.

“She’s been such an inspiration to so many songwriters.”

Holly is determined to have fun on stage and says Swifties have already been supportive, making friendship bracelets for her which fans have been exchanging at shows.

“I feel like I’m gonna be walking out of Wembley with stacks of friendship bracelets and I’m never gonna want to take them off,” Holly says.

“I’m gonna keep them all forever.”

Listen to Newsbeat live at 12:45 and 17:45 weekdays – or listen back here.