Helen Sloan / HBO

Michele Clapton worked on her own fashion line and was a stylist for musicians before embarking on a successful career in costume design for television. Now she’s the Emmy-award winning designer responsible for the lavish gowns and hard-edged armor on HBO’s Game of Thrones. In honor of the third season’s March 31 premiere, she spoke to TIME about how she grounds her sartorial fantasies in reality.

Did you consciously try to move away from a stereotypical medieval fantasy look?

In a way I did. Probably the books are more fantastical. When I first met David and Dan [Benioff and Weiss, series creators] the whole idea was that it was a fantasy rooted in reality. There should be a reason for everything, the way people dress—to keep warm or to keep cool or to protect themselves. It was a very definite move on all of our parts to try and make it real, so that people look at it and aren’t quite sure whether it’s real or not. And then they go, actually no, this didn’t happen, this is not real!

How do the varied landscapes affect the way you dress the cast?

If you’re in the North, you don’t have access to a lot of cloths that they do in King’s Landing [capital city in the South], so you look very much within the radius of what’s there, which is furs and wools and rather murky dyes. So that really dictates how the clothes look. But as soon as you go to a port or somewhere warm, then they can trade and you get vibrant colors and jewels. And I try also to bring in the sigils [symbols for each house]. For instance, the Tullys’ is a fish, and I made their armor reflect that. So there’s a lot of leather scales which we hand-dye; the metalwork is scaly as well.

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Helen Sloan / HBO Costume designer Michele Clapton with a dress worn by Cersei (played by Lena Headey).

Can you reveal anything about what to expect for season 3 in terms of costumes?

Some of the main characters develop battles with each other—in King’s Landing especially, with Margaery arriving on the scene and [Queen Regent] Cersei used to being the woman who was there before, so there’s a sort of costume standoff in there, which actually is alluded to in the script. And that also influences the court. The younger pretty girls start dressing like Margaery a little bit—it’s what would happen, it’s the new princess in town. I think the costume is richer this year. The rich stuff is richer and the rough stuff is rougher.

Are you surprised to see that the show has had an influence on real world fashion trends?

Yes and no. I think it’s so interactive. I’m sometimes influenced by fashion, and I think fashion is sometimes influenced by something which is very, very popular. We put a lot of effort and research into the costumes, so it’s a huge compliment.

How important is function to you in these costumes?

Everyone wears their costume for a reason, and I think what ultimately I’m trying to achieve is that these characters pick these clothes because they suit their way of life, be it in the palace or be it in the field. And some people, the poorer people, do what they can to suit their way of life. So I always try to make it really character-based, and even if it’s something that looks like a bit of a flight of fancy, I hope it works within the respect of the person who’s trying to impress someone or trying to say something.

What do you do to make the clothing look worn?

We have a breakdown department. Especially on the cameras we use, it just shows up so much if something’s too new. I don’t like that—I think everything has to have a little edge. [The breakdown department] often destroys a thing and then repairs it and destroys it again and repairs it. As we go on, we’ve got some great things that have been destroyed in season 1 that are still being used in different guise in seasons 3 and 4, so it’s good. We just re-patch and change and dye and put it up to something else.

HBO is launching a traveling Game of Thrones exhibition this spring. What items do you think fans will be most excited to see?

I think they’re always really excited by the throne. Then maybe the crowns we designed for Joffrey, those are quite cool, and Ned Stark’s costume will be there, which is pretty iconic now.

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