Storing food well has a huge impact on reducing food waste. If you remember that oxygen is the biggest contributing factor in food spoilage, as well as moisture/water, then you will probably start to store your food better.
For example I absolutely hate soft, stale breakfast cereal. You don't need an expensive plastic tub to keep it fresh. Just roll down the packet, pushing all of the air out and use two pegs or an elastic band to keep it in place. And don't forget you can recycle cereal packets with carrier bags at larger Morrisons stores.
This works well if you buy larger packs like crisps. Buying larger packs instead of multipacks means you don't have as much packaging waste. But you need to make sure it doesn't go off before you can eat it all! You can always freeze half a loaf of bread or cake or brioche if you're not sure it will get eaten before it goes off.
You don't need expensive freezer tubs either. Some of my favourite containers to use are old ice cream tubs! They are designed for freezing temperatures and are ideal for keeping air away from whatever you are freezing.
Another item you can reuse for storage is a margarine tub... Perfect for keeping leftovers in the fridge. Jam jars are also good for storing food in fridges. You don't need to buy expensive, pretty, fashionable Kilner jars just reuse jars as you empty them. Or ask friends to keep a few for you.
If you buy bread, bagels or brioche in plastic bags these can also be reused for food storage... Start looking around at what can help keep your food fresh.
Like a lot of eco friendly ideas. A little creativity goes a long way...