Tish Monaghan Costume Designer for "New Moon" talks about dressing Robert Pattinson

From EW.com
You have to immediately like a costume designer who’ll admit that she’s wearing sweatpants while chatting with you from her Vancouver home. We phoned Tish Monaghan, who took over styling duties for The Twilight Saga: New Moon and Eclipse, to talk about how Edward ended up in a suit, why Jacob’s muscles are bulging through his shirt (when he actually wears one), what department mandated that the wolf pack’s jean shorts be extra tight, and more.

ENTERTAINMENT WEEKLY: Anyone who’s listened to the Twilight DVD commentary knows that Robert Pattinson wasn’t a fan of Edward’s pea coat.
TISH MONAGHAN: He wasn’t a fan of the pea coat. He wore it in virtually every scene, and I think maybe he just got tired of it. I’m guessing. [Laughs] He just wanted a more mature look. That was part of Edward’s Grade 11 year, and now he’s getting into his graduation year, he’s in a relationship. He had worn hoodies and jeans and sneakers, and Robert, the director [Chris Weitz], and I all wanted to portray him more as a gentleman, more elegant and classic. With our vampire characters, I always went back to the time period in which they were turned to see if there’s any element I could try to simulate in contemporary clothing. He came out of the Edwardian period, around 1910. Of course, most of the gentleman from that time would be wearing suits, coats, hats, etc. We had to pick something that was iconic for the character that would suffice to be used throughout the whole film. At the very beginning of the film, he has one school outfit, and then there’s Bella’s birthday party and disaster strikes. So Edward ends up in that same costume for the remainder of the film. I was thinking of just putting him in a dress shirt and a pair of pants, but Robert wanted to be in a suit.

So I found a modern contemporary look that would be appealing to him and to the massive fan base, a very slim cut, and a fabric that to me was a bit Old World — this beautiful tweed fabric that we got out of England. It had the gray base, which is kind of essential for the Cullen characters in their cool tones, but also had little interesting flecks of blue, which is also Cullen, and a tiny little bit of rust, which I liked because Bella wears earth tones and that kinda linked her into the picture. The general texture of the suit would hold up well no matter what setting he was in: Inside the house for the party, or in the forest, or in the Volturi chamber. We had to show wear on the suit, and it’s much easier to rough up something that has texture to it than just a flat piece of wool. His pants are worn at the knees, they’re rumpled.

I don’t know if anyone’s looking at his pants when he removes his shirt in Italy.
(Kate: {blush} Emmmm...... no comment {blush})
The fans were very excited to see that, I don’t know if Robert was particularly excited to perform that in front of 1,500 people. I think it was quite hard for him to do. We originally tested Edward in a plain white shirt, as a forlorn-looking option. That is also what Robert wanted — he wanted something that would wash him out. But you need to have a color that makes you pop, and so we actually dyed the fabric this beautiful ink blue ourselves. It highlighted his vampire white skin really well. I think it’s a great moment when we see him in these clothes that he’s worn from September to May. When he goes to sacrifice himself, he’s in disrepair. Robert and Chris wanted his shirt to have a rip across the chest, so that’s what we gave him. It’s really kind of tragic to watch him take off his shirt, because he really is sacrificing himself. It looks like he’s just giving up. He’s exposing himself and he’s completely vulnerable, and he just takes his shirt off and he drops it at his feet with his eyes downcast. Then he gets attacked by Bella, who shoves him inside the doors. [Laughs] I don’t find it like a beefcake moment. It really is a moving moment, and I think Robert did a really amazing job for that scene.

The tear across the chest was to symbolize that his heart was torn out when he thought he lost Bella?
Maybe. [Laughs] They just said, “Rip it across the chest.” I said, “Are you sure? No shirt’s gonna rip like this.” And they said, “Yes.” So I did it.

Why couldn’t he remain shirtless for the indoor fight scene? Why put on the robe? Originally, the guards who grab him were supposed to be coming from the outside — that’s why they give him the robe. But the setting was changed, and they grab him on the inside. So why do they hand him this robe? Because, quite honestly, it looks very cool fighting with this long, flowing garment, and it does hide pads, protect him.
To read the parts about Jacob etc go here