Check the queue at the main till, and weigh this up against the number of items you have in your hand (a litre of milk, a chocolate bar, a toothbrush and a small bag of salad).
Make the decision that scanning these four items at the self-service check-out can't possibly take longer than waiting in the assistant-serviced queue, especially as the current customer, a fur coat-clad woman, is arguing about the supermarket running out of GM, gluten-free, diet, sugar-free, fat-less doughnuts and having to pack her own bag. This despite the fact that the assistant, who, although half your age, is certainly worth you standing there and being mentally undressed by you as you wait. But you sensibly opt for speed over a very attractive young woman.
Press “Begin”, and scan in your loyalty card so the machine can spit out some extremely “relevant” offers when you have completed your purchase, thus proving that the supermarket knows everything about you - your buying habits, your shirt size, where you live, when you went on holiday, the car you drive, the TV channel you watch and the number of times you have partaken in unprotected sex during the past month.
Select “I am using my own bag”, because as even a social ingrate wouldn’t want to waste a bag on so few items, so why should you. Be green, as it may just impress the lovely checkout assistant that you now regret not mentally undressing fully and completely while waiting to be served. Besides, you’ve brought along the Hessian “bag for life” you bought three weeks earlier.
Place your Hessian “bag for life” in the bagging area, as directed, so that the machine can “verify your bag”. You have already verified that the fur-coated object arguing with the extremely delightful checkout assistant is indeed also a bag.
Become completely confused and frustrated when the machine cannot “verify your bag”. Could this be because the bag is from Waitrose and you are currently shopping in Sainsbury’s.
Push a few buttons, swear at the screen and look pathetically at other customers while you try to verify your bag. It's hessian, smells of hessian and has a big “Waitrose” on the side - how can it not be verified?
Take a deep breath and stop looking at fellow customers for help when the machine suddenly seems to give up on verifying your bag, and allows you to continue, even though the chances are it will now be charging you for using you own bag – because it’s from Waitrose.
Now, scan first item and place it in what you hope is now your ‘verified’ bag. Phew! It’s working. Now you can start to believe it's actually going to work fully this time.
Scan your second item. Begin to blubber uncontrollably as the machine bellows “unexpected item in bagging area”, attracting the attention of everyone for miles around you in this small, city-centre shop.
Wait patiently and innocently for a member of staff, preferably the lovely undressable one, to take a break from the busy service tills to press a button on your infernal self check-out machine. Instead, you get the late-aged grandma who can’t understand why a man over half her age can’t operate a simple piece of machinery.
Place your second item in bag and then scan your penultimate item. Place third item in bag. Suppress any feeling of elation that perhaps this will work. But work it actually does.
Scan final item. It’s only a bag of innocuous salad, but the machine bellows “age verification needed”. This is the first time you knew there was an age rating for lettuce and rocket.
Wait patiently and innocently again for a member of staff, giving up any hope that it will be the lovely undressable one, to come over to verify that, yes, you are indeed the correct age to purchase lettuce and rocket, and to press the magic reset button. Maybe like the machine, she’ll believe you indeed are much younger than you are and insist you take her out on a date, marry her and have lots of children.
And lo and behold, the lovely undressable one it is, and in your excitement, you drop your milk and the carton explodes all over the top of the infernal machine as well all over the lovely undressable one’s trousers.
You sadly realise that she is most certainly not going to ask you for help in removing them to dry them.
Press 'Finish and Pay', and yes, you have scanned in your loyalty card. All to gain the equivalent of 2p discount on this particular £3.12 set of purchases.
Count out the required amount of money, £3.12
Put two £1 coins in machine, followed by two 50p pieces, a 10p and a 2p and wait patiently while the machine counts this vast amount of coinage (6 pieces) you have put in.
After 5 minutes, you come to the conclusion the machine is not going to recognise 12p of your payment. Start to blubber while considering if it might be worth adding another 12p if only just to finish with this awful encounter.
But you decide that, philanthropic or not, Lord Sainsbury is wealthy enough without an involuntary donation of 12p from you, so being thrown a lifeline, you agree with the machine and press the “Help” button
Realise that the queue at the check-out with the real person has just served the last person who came into the shop after you.
Explain your plight to the very helpful and understanding and very important-looking Sainsbury’s chap with the X-Factor microphone and headphone system on his head, who, in between barking out Star Ship Enterprise-like instructions to more junior members of staff as to how to restock the baked beans, looks at you with total empathy, understanding, support and a heinous big grin on his face.
He disappears off to the help desk to get his keys for the machine.
Watch as Sainsbury’s chap returns, opens the machine, unlocks the cash box, grabs 12p, locks the cash box, and then closes the machine again.
Plonk the 12p back in, this time successfully, while at the same time thanking Sainsbury’s chap for his help. (‘Anything else I can help Sir with today?'). Avoiding suggesting he might care to settle your credit card repayments in full, pay for your TV licence and buy you a car, you politely decline, thanking him for his time, while at the same time resisting the temptation to ask if Anthony Worrall-Thompson has ever shoplifted from this branch.
Try to look relaxed as you leave the shop with your head held high, newly purchased possessions in hand, now worryingly nearer to their sell-by-date than when you first entered the store, and regretting that you couldn’t get your hands on the extremely attractive checkout assistant. Anyway, she’d be no doubt reeking of milk by now.
Realise that when you went in, the Spring buds were on the trees, and the nights were getting shorter. As you leave, you’ve noticed the leaves have all fallen, Christmas decorations are being put up and you have over 6 month’s beard growth.
You swear not to use self-checkout ever again. Until next time. Which is tomorrow and an excuse not just to check out your shopping, but to check out the extremely attractive check-out assistant.