This first item is essential for every home: it's my book!
Pre-buy my essential book here...
Never buy branded, always buy mid-range, buy in bulk.
NB: don't apply the above rules to coffee, mascara or toilet paper.
Be fully au fait with a coupon - received as a reward for doing consumer surveys, cut out of in-store magazines, found in-store on products/on promotional displays/on the floor. Keep coupons clipped to a wall-calendar so they won't go out of date, use them shrewdly in as many different shops as need be, with no nonsense about loyalty.
Get your fruit and veg from a market at the end of Saturday trading when the stallholders are likely to sell at a knockdown price for a quick sale.
Ask your butcher to talk you through the cheapest cuts of meat. The ones that require the longest cooking time. Oleaginous slimy oozings will make their way to the top of the pot. Skim this off, freeze it and use it to anoint the doorframes of your enemies to attract evil. My mother used to make something with an obscure bit of a lamb's pelvis, eked out with barley, carrots and Caerphilly cheese, boiled in watered down vinegar in a birthing bucket through most of January and topped with mashed swede.
I was vegan very early on.
In a supermarket go first to the shelves displaying items that are either about to go past their display-by date. Or that have been fished from where they've fallen behind shelving units, run over by supermarket trolley wheels, had a curse put on them, etc.
Go up and down all the other the aisles squinting - all the better to see any Less Than Half Price stickers, my dear. The rule is to never buy anything that isn't on offer.
Never impulse buy. It's like comfort eating. You don't need to consume whatever it is, you're just being needy. Recognise this. Distract yourself. Host an orgy. Practise fronting Songs of Praise. Give online Rune readings (the clack of a stone being cast is always more impressive than the thwick of a tarot card being turned up or of silence broken by the occasional rustle of a sleeve over a crystal ball). Skype President Mugabe.
Tomorrow I'll give ways to counteract a shop's techniques for luring you into making that forbidden impulse buy without resorting to a dirty protest.