The stylish woman's guide to sale shopping

You don't have to sleep on a pavement to get the best out of the Boxing Day sales. Harriet Walker speaks to the buyers from Britain's most exclusive boutiques and asks them what to look out for.

Suzanne Pendlebury, womenswear contemporary buyer at matches

The key to sales shopping is to plan ahead – don't randomly decide to look without having something specific in mind, as it can end in disaster. Luxe sportswear is sticking around for next season, coloured denim is also still strong for spring – great now with a chunky knit and then with a simple white T-shirt as the weather warms up. Try to buy pieces that will work with your current wardrobe and are true to your style. A good white shirt is a key item for next season, as is a great piece of knitwear, which is always a wardrobe staple. Don't buy something just because it appears to be a bargain – step away from the item and ask yourself, "Would I usually wear this if it wasn't 70 per cent off?"

Eleanor Robinson, buying manager at my-wardrobe.com

Shop for brands you aspire to but don't normally have the budget to buy. The biggest mark-downs quite often apply to the top end, which means you may find yourself paying as much as you would normally spend on a mid-range piece at full price but it will be from a brand you love and turn into an item you will treasure. Buy out of season, such as T-shirts in winter and coats in summer. The bargains are all the better and these are things you will always need. Just because something's cheap doesn't always mean you should buy it. Ask yourself: "Is this good quality, does it suit me, what will I wear it with and when?" Once you have made your mind up, don't dither, because sizes sell out quickly. With e-boutiques, register for the newsletters so you are the first to be notified of the new reductions as they happen online.

Rebecca Osei-Baidoo, womenswear buyer at Browns

It's great to find classic pieces that aren't too "trend-driven" – these will always remain wardrobe staples. Although outerwear was a big trend for autumn 2011, there are luxurious coats to be found and pieces that will be in your wardrobe for seasons to come. Chunky knits and knitwear in general were equally as important and there are also some rich cashmere pieces that are great buys. When shopping at sale time, it is best to avoid items that have heavily influenced the high street and to keep focused on pieces that will suit your lifestyle and personality.

Laura Larbalestier, Designerwear buying manager at Selfridges

Have a plan before you start shopping. Make an informed decision about an investment piece that you've been lusting after or a few smaller pieces to buy as a treat. If you can't narrow down the options, think about spring trends and your favourite brands and collections.The globetrotter trend and prints were big last season and have carried over into the new season too. It's a great time to buy coats and jackets. A leather Givenchy jacket from the pre-fall collection isn't season-specific so will be a great investment. It's also the time to buy basics – from J Brand and Paige denim to James Perse T-shirts and Equipment shirts and to stock up on casualwear. Avoid wintery things ahead of spring, as you won't get enough wear out of them, whereas jackets, dresses and basics give a much bigger return.

Stephanie Jones, womenswear buyer at Liberty

Always go for pieces which have longevity. Knitwear and coats are great sale pick-ups as we've only just entered the cold spell, so we'll still need those layers for a few months. Look out for timeless pieces which aren't tied down to a season. Invest in a great jacket, such as the Acne navy wool Tate blazer. This lightweight jacket is a really versatile piece that you can dress up or down. Autumn 2011 has been full of vibrant colours and the rich burnt orange of this Draw in Light slouchy printed T-shirt is a great way to do that pop of autumnal colour through the winter – fab with a pair of skinny jeans. It's always tempting to get carried away by a bargain, but I'd recommend going for transitional pieces that you know you'll get wear out of and will carry you through to spring.