(Models wear Stella McCartney, shot by Erik Madigan Heck for Harper's Bazaar)

The idea of creating a sustainable or ethical wardrobe from scratch is, without doubt, a daunting one. Not being able to wear the brands you are used to, limiting your choices in terms of trends, having to spend a little more than you would normally?

All of these concerns are of course valid, but it isn't as hard as you might think to get started on a sustainable wardrobe – and it's definitively worth it in the long run.

Here, we have rounded up 10 tips from the experts on how to have a more sustainable wardrobe, without very much effort at all.

1. The 30 wears test

Livia Firth, the founder of Eco Age (a company which certifies brands for their sustainability) began the #30Wears campaign to encourage us to only buy an item if we really know that we'll wear it.

She told us: "The biggest message is every time you buy something, always think, 'Will I wear it a minimum of 30 times?' If the answer is yes, then buy it. But you'd be surprised how many times you say no."

Try to veer away from buying that statement piece you know you are only going to wear for one occasion, and instead invest in something with more longevity that you can wear again and again. Pick more versatile pieces that can be styled in different ways, rather than that one item you know is going to fall out of fashion in no time.

2. Be more informed

One of the most difficult things about trying to be more sustainable is knowing where to start – and more importantly, where to shop. In this day and age, however, it is much easier than it once was as there are so many brands that are run with a sustainable focus in mind.

Tome, Reformation, Aitch Aitch, Amur, Article22, Zady, Kitx, Veja, Bottletop and Lemlem are all recommended and certified by Eco Age (more of their clients this way). Here, we have rounded up a list of eco warrior Emma Watson's recommended sustainable brands – and don't forget to keep an eye out for sustainable ranges in some of the high street's biggest shops, like H&M's Conscious Collection.

Do a little investigative work, find a handful of brands you love and start from there. After a while, your portfolio of knowledge will have grown – and you'll have a whole host of brands to choose from.

Emily Ratajkowski wearing Reformation. Image: Rex

3. Shop vintage

"Every new item of clothing made has a substantial carbon footprint attached to its manufacturing; but the amount of new energy needed to produce vintage clothing is zero," Emma Watson said on her Press Tour account. "Vintage clothing has a huge role to play in making fashion more sustainable and reducing a global footprint that includes the 132m metric tons of coal used yearly through the production of new fibres, dyeing and bleaching of garments and the 6-9 trillion litres of water used by the industry."

William Vintage, Vestiaire Collective and Edit Second Hand are all great options. More best designer resale sites below.

4. Invest in trans-seasonal clothes

Only buy items that you know are going to work for you all-year-round. Don't shell out on an entire summer wardrobe each year when you live in cold and rainy London – you won't pass the 30 wears test. Instead, spend the bulk of your money on pieces that will see you through more than one season. Jeans, T-shirts, classic dresses, timeless coats and jackets will make for a much more sustainable wardrobe.

Emma Stone wearing a Gabriela Hearst coat. Image: Getty

5. Donate your unwanted clothes

Donating your unwanted clothes to a good cause, rather than leaving them hanging in your wardrobe will help others to be more sustainable, who will invest in your old pieces, rather than buying something new. A great way to do this is to have a one-in, one-out policy – live by the mantra that every time you buy something, you'll donate something else in your wardrobe.

6. Look after your clothes so they last longer

It sounds obvious, but it's so important. Of course if you are buying better quality clothes, they are likely to last longer (and you're also more likely to treat them better because they were more expensive) but this goes for everything hanging in your wardrobe. Look after them properly and you will have to replace things less often. From caring for your cashmere to washing your denim inside out, go the extra mile to ensure your clothes stay at their best for longer.

7. Learn how to repair clothing yourself (or find a good tailor)

When something rips or a heel breaks, you don't necessarily have to throw it away. Learn how to repair your clothes and accessories – or, even easier, pay a professional to do it. Think twice before before using it as an excuse for something new.

8. Go for quality over quantity

It's all about planning. Buying better quality, more sustainable pieces is likely to cost you more money than buying a cheap high-street product that doesn't tick the right boxes. However, it's all about changing your mindset. Yes this costs more, but I am only going to buy one. Buying 10-30 high-quality items a year, rather than 60 cheaper, less eco-friendly pieces will dramatically reduce your carbon footprint. Basically, save up, invest and buy less.

9. Adjust how you spend your money

Change what you splurge on. Instead of spending your savings on a dress for a wedding or a pair of shoes you will only wear for special occasions, spend your 'investment' cash on the things you wear every day. Stop thinking, 'I would never spend that much on a pair of jeans,' consider that you are only going to buy one pair of jeans this year, or one item this month – and make it this. After a few seasons, you will have a high-quality, sustainable wardrobe to be proud of.

10. Change your perspective

"I don't think that 'eco' should be a word that immediately conjures up images of oatmeal-coloured garments or garments that are oversized or lacking in any sort of luxury or beauty or detailing or desirability," Stella McCartney writes on her website. "I don't think that things have to look ugly because they're organic; why can't they be beautiful as well? You can't ask a consumer to compromise. I don't think you can say, 'Here is this jacket that looks terrible but it's organic, and here is a really beautiful jacket that's cheaper but don't buy it because it's not organic'."

With more and more brands seeing the importance of an environmental focus, dressing sustainably no longer means compromising – so stop thinking it does.

Models on the Stella McCartney catwalk. Image: Getty