Some of my most ill-judged purchases have been made at a discount - an ice-cream maker destined straight for the appliance graveyard under the oven, and that lurid-pink pasta spoon. Both utterly resistible had they not been on special offer. But I’ve learnt to be sales-sceptical. Here’s the thing: sales aren’t for shoppers’ benefit. They are part of the bigger retail game, in which we consumers are mere pawns, so approach them with a proper degree of circumspection.

Pitfalls for the unwary shopper are legion. One common retailing tactic is to keep the pieces we really want out of the sale, leading us to buy something we don’t need, in the wrong colour, just to make our shopping expedition worthwhile. (Which surely explains why so many faux zebra-skin cushions are sold.)

Another ploy used to be to mark an extra-high presale price on the ticket, scored through and accompanied by a much lower sale price. But no more: trading-standards guidelines brought in this May stipulate that a product must have been offered at that price for more days than it will be discounted for, rather than for 28 days, as was the case before. And don’t allow yourself to be daunted by signs saying that sale goods cannot be returned: they can if they are faulty. The Sale of Goods Act 1979 covers goods in clearance sales every bit as much as items bought at full price.

Enough of the negative: the good news is that, forewarned against the hazards and forearmed with appropriate rules of engagement, the sales-savvy shopper can find ways to turn the system to their advantage. And now is the time to strike. Over the next two weeks, during the last days of the clearances, there will be even heftier discounts.

Rule one: Don’t be lured by the lowest price; instead, try to get a good deal on the most sought-after designs. Heal’s is offering a handful of its bestselling furnishings in its sale (www.heals. co.uk ; sale ends July 27; stores in Brighton, Leeds, Manchester, London, Kingston, Guildford and West Yorkshire). Among them are the Cross oak dining table by Matthew Hilton (was £1,450, sale price £1,160) and the Designers Guild Amalienborg rug (was £690, now £552).

Ligne Roset also has discounts on some of its most popular designs: a large Togo sofa in Alcantara is £1,585, down from £1,865, and the Lunatique table has been reduced from £534 to £481 (www. ligne-roset.co.uk; sale ends July 31; stores in London, Manchester and Edinburgh). At Purves & Purves, Matt Carr’s Pisa bookshelf in dark wood veneer now costs £195, down from £250 (www.purves.co.uk; sale ends July 31; store in London).

Rule two: Decide whether you are a serious stocker-up or a magpie, then adopt the appropriate strategy. Serious shoppers use the clearance sales to swoop on investment pieces they’ve had their eye on all year, often sticking to neutral colours and classic designs. Research is key: these bargain-hunters know the precise model they want and the exact moment the sale begins. Best buys for stockers-up are big-ticket items, including kitchens and bathrooms. John Lewis of Hungerford is discounting its Cool Kitchen range, with as much as £3,000 off its “piano gloss” kitchens, usually priced from £15,000 (www. john-lewis.co.uk; sale ends July 28; stores in Bristol, Cambridge, London, Harro-gate, Hungerford, Oxford, Tunbridge Wells, Wilmslow and Winchester). At Bathstore, which has more than 170 stores nationwide, a Winchester free-standing rolltop bath, normally £399, is now £299; the Esprit back-to-wall free-standing bath has had its price slashed from £899 to £699 (www.bathstore.com ; sale ends August 17).

Magpies will have a less stressful time of it: there are plenty of colourful, mood-enhancing treats for less than £20. The vivid tableware at Skandium is a case in point: Tris candleholders, by Iittala, are chunky triangular numbers in flamboyant hues (were £29, now £14.50; www. skandium.com; sale ends July 31; stores in London). Luxury bed linen and towels are also favourites. Harvey Nichols, which has stores in Edinburgh, Manchester and Leeds, as well as London, has discounts of up to 70% on cotton percale bed linen, silk cushions and throws, along with 800 gsm towels from the Bed by Conran range. An opulent deep-blue kingsize duvet cover by Descamps, normally £120, costs £84 in the sale (www. harveynichols.com ; sale ends July 27).

Rule three:Many stores do business via shops, catalogues and websites. Before you buy, find out which channel offers the best deals. In the Emma Bridgewater sale, for instance, some discounts are available only online, including a heart-strewn double oven glove, down from £13 to £8 (www.emmabridgewater.co.uk; sale ends today; stores in London, Edinburgh, Stoke-on-Trent and Trentham). But don’t assume that everything will be cheaper online. Bridgewater’s best deal is being offered instore as well as on the internet: a set of six spongeware-decorated pottery plates in a polka-dot pattern, which normally costs £90, is currently priced at £40.

Oka, which started life as a catalogue company, always gives its database of mail-order buyers first look at its sale, so get yourself onto the mailing list. “It’s an important part of our strategy that our loyal customers see our sale first,” says Miranda Christie, Oka’s marketing director. “Twice a year, they know we will have some really good bargains for them.” An attractive foldaway computer cupboard is outstanding value at £390, down from £860 (www.okadirect.com; sale ends August 22; stores in London, Saffron Walden, Sunninghill, Edinburgh, Froxfield, Berinsfield, South God-stone and Haslemere).

Finally, the timing of your purchase is crucial – which means you may have done well to wait until the last days of clearance. Most stores are unwilling to discuss quite how low they will go, but at Heal’s, where a spirit of openness prevails, they cheerfully disclose that there will be reductions of up to 70% in the last week. So, from tomorrow, you have a sporting chance of getting that Matthew Hilton table for £435.

Don’t be shy about asking for a bigger discount, especially in these final days of the clearances. In a larger chain, sales assistants may not have the authority to accommodate your cheeky request, but the proprietor of an independent shop will always be able to do a special deal. If that doesn’t work, most stores will have seconds or ex-display furniture, which they will happily sell for less. In these belt-tightening times, you can make significant savings this summer. The real trick to sales-savviness, though, is to go home before you start eyeing those pink pasta spoons.

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