Olivia Colman has learned clothes can make her feel "strong and powerful".
The 45-year-old actress had always used her outfits as a "mask" but suffered a breakthrough with her "crippling" red carpet nerves when she wore a particular outfit and felt more confident than every before.
She said: "A lot of people take on a pretend persona, but I'm crippled by it. I feel embarrassed.
"A breakthrough for me was at the Venice Film Festival, wearing Stella McCartney. I felt, I can do this, I can do this.
"I'd always used clothes as a sort of mask. I discovered that they can make you feel strong and powerful." In other words, more truly oneself."
The 'Crown' actress was never confident in her looks when she was younger but looking back now, she thinks she was "beautiful".
She told America's Vogue magazine: "I look up pictures of myself as a teenager, and I think I was gorgeous. But I didn't feel that.
"All those little comments through those precious years can have long-lasting negative effects. You see images of a perfect person and say, 'I can never be that.' "
And these days, the 'Favourite' star - who has three children, Finn, 14, Hall, 12, and a little girl aged four, with husband Ed Sinclair - doesn't care what people think about the way she looks because she knows she's a "nice" person.
She said: "Over the years, pounds have gone on, and my body has changed; I've had children.
"If someone doesn't like me because of the size of my bum, they can f**k off. Because I'm quite a nice person to be with, actually."