Even when Grace VanderWaal was competing on America's Got Talent last year, she seemed wise beyond her years -- at least for someone who hadn't even reached her teens yet.

The then-12-year-old (who turned 13 on Jan. 15) impressed the judges and the country with her sweet-yet-masterful ukulele playing and captivating voice, eventually doing so all the way to the finale, where she was crowned the season 11 winner. But six months after her life-changing win, VanderWaal is already working hard on her debut album, moving on from the label of America's Got Talent winner to singer-songwriter.

One of her most recent showcases took place in Las Vegas -- where she headlined three nights at Planet Hollywood Resort & Casino in October -- taking part in One Night for One Drop, a charity event benefiting critical water issues worldwide and featuring Cirque du Soleil artists as well as other stars. She got the opportunity to perform her song "Light the Sky" during the event (which took place March 3) but in a not-so-familiar getup: a harlequin clown costume.

"At first I was a little iffy because I was like, ‘It’s the circus, is this going to be awkward? I’m not that kind of person… is there just going to be like dancers behind me while I sing?’" Grace told Billboard backstage at rehearsals. "And then when I got here I was like, ‘This is the coolest thing ever!’ I’m so happy I did it, and I want to do this next year too."

VanderWaal's performance was as pure and impressive -- if not more so -- as what she displayed on America's Got Talent, and while she has already released the five-song EP Perfectly Imperfect, she's looking forward to releasing her first full record later this year. With no set time frame for when that is coming, though, Billboard got the scoop on some of her biggest takeaways since her big win, her relationship with Simon Cowell (who signed VanderWaal after AGT), and if she's gotten that tree house she wanted from the moment she auditioned.

What it was like winning a million dollars: Well, I'm a child, so I didn't win a million dollars. But it was so cool, because I got to use that excuse for everything. Obviously not every kid in America gets everything they want, so whenever I’d ask for something, like a pack of gum or something stupid and my mom would say no, I’d be like, “I just won a million dollars, I can pay for it!” I used it for a month and then my mom was like, “Well you don’t, Grace, you don’t have a million dollars.” [Laughs]

If she's gotten her tree house: No! It’s the most confusing thing ever -- it’s like building a house. There’s all these contracts, things you have to go through. This is a house in a tree and you’re acting like we’re building a literal house! But we are getting it, it’s in the works… hopefully soon.

What's changed since AGT: It’s been a year [since auditioning], and it’s unbelievable to look back at myself because I have changed so much. And not in a bad way at all; in the best way possible. It’s an organic change -- I’m young, so I change a lot. It’s really been confidence, personality-wise at least. The one thing that really hasn’t changed is being onstage. I am more confident onstage now, but ever since the very beginning, it felt so natural.

What's kept her grounded: My family. Child stardom is a really hard thing. It can really lead to bad things and I think a lot of people have gone through that. And when you look at a lot of them, they’ve gone crazy and they didn’t really have a good family foundation. Even though every family has its struggles, it’s still a good relationship, and I think that’s the main thing. I’ve also gotten into meditation, it’s really great.

Her relationship with Simon Cowell: He’s the sweetest little muffin ever. I love him. He’s always calling me and checking in, like [in a British accent], “Grace, are you OK? The album’s going great, I’m just so proud of you.”

What her debut album will be like: This is definitely my more "I don’t care" album, like I don’t care what anyone else thinks about it. I definitely want it to be more produced because that’s what I like and that’s me. I think I get too hung up on what people think about it. I'll never make everyone happy, so why do I even care anymore?

I’m still really the same sound, because I can’t really change my style or else it will feel forced -- and I always think that definitely shows through. It just won’t be a good song because people will hear that it’s kind of forced and not organic. It’ll be less acoustic, though, and kind of how I envision the songs when I’m writing.

Her experience with writing sessions: Every single one I’ve had so far were pretty uncomfortable in the beginning, because songs are the most personal thing ever, so it’s hard to write a deep song because you literally walk into a room, introduce yourself, and then say like, “Let me completely open up to you about my personal life.” [Laughs] But once you’re on a roll, it’s not uncomfortable.

What she's learned since working in the music industry: Always be kind, but kindness doesn’t mean that you have to not say what you think. I feel like so many people get tripped up on that, and I got tripped up on that on AGT. You really need to learn that you can be kind while still having your opinion and telling people, “I want to do this.” I think that’s a really important thing to know if you’re ever going into this. If you let yourself be stumbled around just because you think that that’s kindness, you’ll end up a hot mess.

Best advice she's received: "Follow your gut." That’s such a cliché thing to say, but it’s so true. I’ve literally experienced things myself where people are telling me that is the worst idea ever and "that will end your career, it won’t work" -- but something inside of me is just screaming to do it. So I ignore them. Not saying to ignore people, but it works out.

Her most gratifying post-AGT moment: I love it when people refer to me as a singer-songwriter. I get flutters in my stomach, because they say, “This is Grace VanderWaal, singer-songwriter,” not, “This is Grace VanderWaal, winner of America’s Got Talent.” I’m so proud of that, it's such a big chapter of my life. But it’s nice to kind of not be known as just that.

If kids have told her she's inspired them: Yeah, all the time. Even adults and young, 19/20s…That’s the amazing part of humans -- it’s so weird how one person can inspire. It doesn’t matter who you are, and it’s so unbelievable to think about and see right before my eyes. I’m just so thankful.