Use the Salisbury Library of Things for expensive items that you might only use once or twice - whether it be gardening tools, camping equipment, electrical gadgets - they have an amazing variety of useful things to borrow.
Find use around the home for jars, cardboard cartons, plastic wrappers and other packaging where possible.
Make a compost heap or invest in a compost bin so that you can use kitchen/garden waste as a resource for the garden - discounted bins are available through Wiltshire County Council www.wiltshire.gov.uk/reducing-your-waste-and-composting
Use cast offs or fabric remnants in craft activities or to make items for the home, e.g draught excluders, bunting, dolls clothes.
Give a new life to things you no longer want or need - donate to local jumble sales/charity shops, M&S's "Shwop Drop' box; use Freecycle or eBay.
Look out for, or set up, local 'swap shop' events - or maybe just swap with friends!