Inside Elle King’s Say Yes to the Dress Fitting: I Knew Which Wedding Gown Was ‘the One’ When My Mom ‘Ugly-Cried’

Warning: This story contains spoilers.

“America’s Sweetheart” will soon be walking down the aisle in style thanks to a little help from Say Yes to the Dress.

In July, Elle King dropped by the iconic N.Y.C. boutique Kleinfeld Bridal to track down a wedding gown, and PEOPLE was there for the filming of the episode, which will air Saturday on TLC.

“People take months to find their wedding gown, their dress, and I knew that I wanted to try on a few styles — because I didn’t know! So if you want the best, you go to the best. I booked my appointment at Kleinfeld because once I set the date, my mom was like, ‘You better get the appointment at Kleinfeld!'” King tells PEOPLE. “So I made the appointment, and I sent out the screenshot to all the women I know, and before I knew it, they were like, ‘Do you wanna be on the show?’ And I was like, ‘Yeah!'”

For the fitting, the Grammy-nominated singer — whose boyfriend Andrew “Fergie” Ferguson popped the question in February of 2015 — brought along her mother, model-turned-doula London King, cousin-bridesmaid Hannah, and pal (and former Teen Vogue editor) Andrew Bevan, who will also officiate her nuptials.

Decked in black leggings and a black-fringed leather jacket, King took a stroll around the store, telling sales associates about her fiancé (“Fergie’s Scottish, so he’s gonna wear a kilt, so nothing will match”); her personal style (“Boho chic does sum up that kind of feel because I want to accentuate certain parts of my body and hide other parts of my body”); her preferred silhouette (A-line); and the three words she wants guests — and her groom! — to say when they see her on the big day: “beautiful,” “romantic” and “damn!”

“Little me is coming out!” King, 27, squealed at the start of her visit, before Say Yes host Randy Fenoli pulled an assortment of looks for the “Ex’s and Oh’s” rocker, from poofy princess and traditional ball gown to glitzy mermaid and whimsical sheath.

Throughout the hours-long fitting, there were tears both happy … and less-so, with mom London exclaiming, “I’m gonna be the most-hated mom in America!” after leaving her daughter misty-eyed after dismissing one of King’s favorite dresses of the day.

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By the end of the fun (and, at times, tears-filled) day, King found the dress of her dreams.

“I tried on maybe six or seven gowns, but none of them mattered,” she told PEOPLE the day of the fitting of the number she chose. “I saw Randy bring it in, and I remember being like, ‘Something about it is special.’ I saw it peeking out when he cleared away some dresses, and before it even hit my shoulders, it was like at my waist, I just knew — I have chills thinking about it. I just totally knew. My mom was like, ‘Baby, that’s it.’ I burst out into ugly tears, and then we went out, and I said yes to the dress, came back in, and my mom ugly-cried, so I knew it was truly ‘the one.'”

As for why King decided to let TLC tape her dress search? Aside from being a fan of the show, “People know me from my music, and my persona is built around heartbreak. I want my fans to know that you can find love and be happy,” she says.

To see which dress Elle King says yes to, watch Say Yes to the Dress on Saturday, March 4 on TLC.

What kind of dress do you think the rocker should wear on her wedding day? Sound off below in the comments!