The actress Mischa Barton, 21, became a fashion icon after she starred in the TV series The OC. She started acting as a child, and appeared in The Sixth Sense and Notting Hill. She was born in London, and attended a RADA course there last summer, but has lived in New York since she was a child. She is the “brand ambassador” for Keds trainers.

I prefer dressing my two dogs to dressing myself. I don’t force them into designer clothes but I always put them in costumes for Hallowe’en or Christmas. I dressed one as a bumblebee and the other as a ladybug. I don’t really approve of making dogs wear clothes all the time because I think it can upset them, but the smaller one actually needs a sweater in New York in the winter. However, she will just rip it to shreds with her paws if she can.

I had absolutely no idea how much attention my clothes and I would get when I first started in The OC; it was phenomenal. Knowing I could be photographed by the paparazzi at any time while I’m hanging out in New York doesn’t actually make me dress differently or wear more make-up, although I do take routes where I’m less likely to be photographed. Also, I’m not that worried about being caught slobbing out because I’m not a sweat-pants and Uggs kinda girl. New Yorkers don’t really get more casual than jeans and a T-shirt.

Some people dress up specifically for an occasion, but I do it for myself because I love trying out different looks; I’m a clotheshorse. It’s an extension of my personality and I have clothes lying all over my apartment. It’s not a dedication to fashion so much as my personal sense of style.

My dress sense is eclectic because I pick things up everywhere I go. My mum grew up in the 1960s and 1970s and I think that influenced my style a lot because I love vintage shopping – I’m a real thrift scrounger. I like to mix vintage with designer pieces because my pet peeve is people who wear the same label head to toe like a uniform; or really blatant logos all over their clothes.

I don’t think that I’m extravagant when it comes to shopping but then again I have no clue what the most I’ve spent in one go is.

My favourite labels are Chloé and Chanel, who have always been very good to me for red carpet events, and Balenciaga. I also love Zac Posen and Matthew Williamson, and since I have become friends with them they have made me clothes.

I use the stylist Rachel Zoe for red carpet events. I chose her because she is a friend and I would go over to her house and see all these amazing clothes. I used to call the designers myself and ask them to send me stuff, and pick clothes out of magazines, but the nice thing about working with Rachel is that she knows what I feel comfortable in.

I was born in the UK, and I have some of that English refinement in the way I dress. When I was a child my mum would dress me in a typically English way. I went to St Paul’s school in London for two years – so it was all about mary janes, blazers and boaters. However, I think I have quite a New York grooming sensibility as well.

I am always being asked if I will design a clothing line, but my first love is acting and everything else is peripheral. Actually, I do love clothes, so maybe I will. They would have to be pieces I would actually wear because I am such a hands-on picky person.

Times recommends

• Live chat: Thrifty ways to update your winter wardrobe
• Is anybody out there really listening?
• Nutrition Q&A: Will eating late make me fat?