Start with what you already have

Before you write a shopping list, spend five minutes with the fridge door open and a notebook in hand. Most of us buy duplicates without realising it — a third jar of mustard, another bag of carrots quietly softening in the drawer. The single biggest saving in the weekly shop isn't a clever app or a discount voucher; it's simply knowing what's already in your kitchen.

Pull everything out of the vegetable drawer and the top shelf, check the freezer, and make a note. Then build your meal plan around the food that needs eating first. That tired-looking bunch of spinach isn't a failure, it's the starting point for tonight's curry.

• Do a two-minute fridge audit on the day you write your list, not the day you shop.
• Keep a "use me first" shelf at eye level for anything close to its date.
• Note what you threw away last week — if it's always salad leaves, buy less salad.

Plan meals you'll actually cook

A meal plan is only useful if it reflects real life. If Wednesday is a late finish and a dash to the bus, don't schedule a complicated roast. Plan for your genuine week: quick pasta on busy nights, a bigger cook on Sunday, and one flexible "whatever's left" evening at the end.

Try planning four or five dinners rather than seven. Leave room for the takeaway you'll inevitably fancy, and for the leftovers that will fill the gap. Build a short list of meals that share ingredients, so a bunch of coriander, a tub of yoghurt or half a cabbage gets used across two or three dishes instead of one.

• Anchor your plan with a base — rice, potatoes, flatbreads, pasta — and vary the toppings.
• Double up on purpose. Cook enough for a second meal you can freeze or reheat.
• Write the plan where you'll see it, on the fridge or the back of a cupboard door.

Shop smarter, not bigger

Multi-buys are designed to feel like a bargain, but a third bag of peppers you won't eat isn't saving you anything. Buy loose fruit and veg where you can — from the market, the greengrocer or the supermarket aisle without the plastic — so you can take exactly three carrots and two onions rather than a kilo of each.

Shop little and often for fresh things if that suits your week. A mid-week top-up from a local shop often beats a giant Saturday haul that wilts by Tuesday. And don't overlook the reduced section: if you can eat it or freeze it that day, yellow-sticker food is perfectly good food.

• Shop to a list, but leave a small amount of flexibility for what looks best.
• Buy wonky or loose veg — same taste, less waste and usually cheaper.
• Only buy the reduced items you have a plan for within 24 hours.

Store it so it lasts

Half of household food waste happens after the shopping is home. A few small changes to how you store things can add days to their life.

Keep your fridge between 0°C and 5°C — most are set too warm — and put milk, meat and fish at the back where it's coldest. Herbs do well with their stems in a jar of water, covered loosely. Salad leaves last longer in a bag with a piece of damp kitchen paper. Keep bananas away from other fruit, as they speed up ripening. Potatoes, onions and garlic prefer a cool, dark, dry cupboard, and they'd rather not sit next to each other.

Bread freezes beautifully — slice it first, so you can take out what you need. Freeze leftover herbs in oil in an ice-cube tray, and bags of grated cheese, chopped veg or over-ripe bananas are ready for future meals. A full freezer runs more efficiently than an empty one, so don't be shy about filling it.

Turn leftovers into tomorrow's dinner

Leftovers are only boring if you think of them as plates of reheated food. Think of them as ingredients instead. A Sunday roast becomes Monday's sandwiches, a midweek pie or a tray of stock from the bones. Roasted veg turns into a frittata, a soup or a warm salad with grains.

• Sunday's chicken → curry, soup, or a stock that's far better than anything from a cube.
• Soft veg and tired salad → blended soup with a tin of beans and a spoon of curry powder.
• Stale bread → croutons, breadcrumbs, or a proper pudding.
• Bendy bananas → loaf, smoothie or frozen chunks for baking.
• Cheese rinds → drop them into a pot of soup while it simmers.

Label leftovers with the day you cooked them, keep them where you'll see them, and eat them within two days — or freeze them on the night you make them, before they slip to the back of the shelf.

Make it a neighbourhood habit

Reducing waste is easier when it's shared. Swap gluts with neighbours — you'll gladly take their courgette mountain in exchange for your herb pot. Local community larders, church halls and food-sharing shelves often welcome spare tins and unopened packets. And if you've a garden or a balcony, a small compost bin turns peelings into next year's soil.

One bin bag of food wasted a week costs the average household a real chunk of money over a year. None of this needs to be perfect. Pick two changes — a proper fridge audit and one flexible leftovers night — and you'll notice the difference in your bin and your bank balance within a month.