If you've slept off the Christmas turkey, ham, Brussels sprouts, pud, cream, chocolates, wine and port, and are now thinking a brisk bout at the sales is just what you need to perk you up, best get prepared.

First, make a wish-list of what you'd like to find. The more savvy will refine this to what they need; the rest of us will just head out there and buy as impulse dictates.

This last is not recommended by the professional sales-goer. But it can be great fun, especially when you get home, open the bags and find you are now the proud possessor of three coffee percolators, another black scarf, a third pair of fashionable hiking boots and a pair of trousers which don't really fit but just might do if you lose a few pounds.

Whatever about the list, good elbows are a must. Professionals will have had theirs sharpened in advance. As for the other extremities, feet are liable to ache, swell, sweat and flag if not properly looked after. Well-shod feet in comfortable slip-on shoes are essential. If you're planning to rehouse those feet, why not go a step further and put on clean socks.

And, still with the glad-rags, hooks and eyes, elaborate buttons or lacing are not the fastenings of choice. What you want is a slip-on, slip-off outfit.

If it's raining, don't, don't, don't take an umbrella. Umbrellas in crowds are a nightmare, while umbrellas in shops are just another item you are bound to leave behind in the changing-room. Umbrellas as weapons? Well, that's a different story.

Before you leave home - with the list, without the umbrella (as we're all good citizens really) - eat a good breakfast. Novices may not realise that all coffee shops, restaurants and canteens will have queues just when you decide you must top up the calories.

Now that you are fed, clad in that gorgeous elasticated waist skirt and that comfortable pullover, and shod in those sensible shoes, try dropping in to expensive shops you would normally avoid. They often have better reductions and the crowds may be thinner. The shop assistants will usually be too polite to comment on your attire.

But seriously, no bargain is worth going into debt for. The Director of Consumer Affairs, Carmel Foley, has been urging people to compare prices and to beware of running up large credit bills at Christmas.

This advice is even more germane now, as your credit card may already be feeling the worse for wear. Foley says people should be aware that many credit cards charge very high interest rates, so make sure you can pay the bill before it spirals out of control.

Many people are under the impression that if they buy an item during a sale, it's not subject to normal statutory controls. This is simply not true. A spokeswoman for the European Consumer Centre (ECC) says consumer rights do not change during sales.

You may see signs in shops saying "no exchange during sales" or "no refunds during sales". These should also state that your statutory rights are not affected. So goods, even if they're substantially reduced, should be of "merchantable quality".

This means they should be of reasonable quality, taking into account what was said about them, what they are supposed to do, the price paid, how long they should last and so on. Goods should be fit for their purpose and they should be as described.

The Office of the Director of Consumer Affairs (ODCA) has produced a useful guide to the Sale of Goods and Supply of Services Act 1980. It states that if goods are not of merchantable quality, not as described or not fit for their purpose, consumers are normally entitled to some remedy.

If the fault or description is not a trivial one and is discovered soon after purchase, you may be entitled to reject the goods and insist on a full refund provided you act promptly. So do keep those receipts and sales tags. A guarantee is a bonus, according to the ODCA, which does not affect the customer's normal legal rights against the retailer. If you have a valid complaint, you can choose to ignore the guarantee; however, it may be easier to claim under it.

Where sales may differ from the normal shopping experience is in the matter of goodwill. During the rest of the year, according to the ECC spokeswoman, many shops will exchange goods or give a refund or credit note even if there is nothing wrong with an item. During sales, however, some shops suspend this goodwill, so extra care should be taken in choosing what to buy. If you're not sure about a particular item, ask about the store's return or refund policy.

What happens if a price tag is incorrect? Sometimes tags can be moved around or misplaced, or items can be wrongly priced. This is more likely to happen during sales, when salespeople are under more pressure. The ECC spokeswoman cautions shoppers that a price is "an invitation to treat". A price tag does not constitute an offer for sale.

You have no right to demand the goods at the price offered; however, a shopkeeper may be guilty of an offence if he or she deliberately gives false information.

So, with all that info and advice, and a good breakfast under your belt, get out there into those shops and enjoy the joust. Remember: faint heart never won fair bargain.

Useful websites: www.odca.ie; www.ecic.ie