When you get back from the supermarket, loaded down with bags and bags of food and the odd magazine and birthday card, what do you do next? You slump down in a chair, then grudgingly unpack all of the things you've bought and send bad vibes to the people whose job it is to price everything, of course! But then what? Based on the average person you will be left with seven or eight plastic bags in various states of crumpled fluffiness. You shove them distractedly into a cupboard or bag (or empty Pringles tube), where they sit taking up space until they are needed for use as bin-bags, or to transport that bottle of wine to the best friend's house.

But how much room do those flipping plastic bags take up!?

Well, there is a solution, you know. It doesn't take fancy bits of wood like the unsuccessful book shelves, or loads of time like the tai-chi lessons.

The Neat And Small Plastic Bag Triangle

This method will give you an end result of a neatly folded up plastic bag, which is about the size of a small hairbrush head. It takes, on average, less than 20 seconds per bag and you can still store them all in that cupboard or canvas bag on the door. They just take up much less space and are more user-friendly when you next come to get them out.

Words Of Warning: Take all receipts, bits of paper, plastic etc out of your bag before beginning. Do not use a sticky or wet bag, it gets messy. If your bag is torn, why are you bothering to make a bag triangle? Throw it away!

1. Take your plastic bag and spread it out flat on a table, ensuring that it's straightened out and not all crumpled up.

2. With the handles or opening at the the top, fold the right side of the bag in by one third, and then the left side in on top of that. You should now have a bag which is a third of the width of the original, with the handles both at the top of the thin rectangle. Run your hand along it from the bottom to the top, squashing out the air.

3. Take one corner of the bottom edge of the bag and fold it upwards and across to meet the vertical side edge, as if you are folding a square of paper into a triangle. Do not start folding from the opening end; you will be left with a big air pocket.

4. Take the point that is now at the bottom, fold it upwards along the horizontal top of the last fold and repeat so that you are gradually moving up the bag length, making a new triangular end each time you fold diagonally and horizontally alternately.

5. After about five to seven¹ folds you will get to the bag handles and not have enough length to make another fold. Take this end bit and tuck it into the inside of the last fold, which should be obvious as a flap pocket right next to the leftover ends.

You have now hopefully made your perfectly-formed bag triangle. It may take a bit of practice but after a while you will be able to do four or five bags within a minute. The important thing is to make sure you keep as much air as possible out of the bag at all times, otherwise it ends up rather messy. Your finished bag triangle takes up much less space than a screwed up bag and is much nicer to reuse.

Occasionally you will fold your bag all the way to the top and find that you've either got no bag left to tuck into the flap, or far too much bag. When this happens, try folding the huge extra bit you may have, into a small triangle and try tucking it in. If this doesn't satisfy, you have to unfold all the triangles back to when you first folded the bag into thirds and then fold it in half again, making it much skinnier. Now fold it back up in triangles again. This should have solved the problem.

If you are a real neat-freak then you can fold your bag so that the label is clearly visible. To do this make sure that the label is face down when you start folding.

If you find yourself overrun with your new plastic triangles then a very good thing is to take them to your local charity shop. This means that the shop does not need to spend money buying bags for purchases, you have more space in your house, and you're doing some good recycling! Or you could take them to your nearest recycling centre. Another good thing to do would be to stuff your triangles in your pocket and set off back down to the shops and reuse the bags. Until you discover you've got nothing left to line the bin!

Happy bag folding!