Only buy the food you know you need, so you don't end up throwing things away. Perhaps do smaller local shops rather than the weekly shop at the large supermarket.
Use any leftovers to make further meals or freeze food you know will go off before you can use it. Eg make tasty soups with tired veg and the chicken carcass or grate stale bread for breadcrumbs, then freeze.
Avoid over packaged goods; use your own bags rather than buying plastic carrier bags
Cut down on the junk mail you receive by signing up to the Mailing Preference Service (www.mpsonline.org.uk)
Turn off lights, computers etc. when you're not using them, and avoid leaving things on standby overnight.
Put on an extra jumper and woolly socks before turning up the heating!
Boil only the water you need in your kettle - and descale it regularly to make it more efficient.
Make sure your home is well insulated.
Wash your clothes at the energy saving temperature of 30 degrees - and if you can, hang washing outside on the line or indoors on a drying rack rather than using a power hungry tumble dryer.
If practical install solar panels on your roof.
Turn off the tap when brushing your teeth.
Use a bowl when washing up and when preparing fruit & veg rather than running the tap.
If you haven't got a low flush toilet, use a 'save-a-flush': free from Wessex Water, along with other water saving devices (www.wessexwater.co.uk/saving water/)
Take a shower rather than a bath (but if it's a power shower, make it a short one!)
In the garden, use a hosepipe with a trigger rather than a sprinkler, and install a water butt to collect rainwater.
Walk or cycle where you can rather than taking the car - good for fitness, too!
Share transport with others, whether public (see www.wiltshire.gov.uk for public transport information) or by car sharing (see liftshare.com/uk/community/wiltshire)
When driving, gain maximum fuel efficiency by driving smoothly, reducing speed, shifting to a higher gear as soon as you can, and switching off the engine if stationary for more than a couple of minutes
Save food miles by buying local produce when you can - and if possible, grow some fruit & veg yourself with zero food miles!
Cutting your fuel use will also help to limit emissions of harmful gases - both carbon dioxide (the major contributor to climate change) and nitrogen dioxide, a serious hazard to human health.
Avoid use of pesticides and weed killers in the garden - they can harm wildlife (including the natural pollinators) and pollute rivers and groundwater.
Dispose of awkward things like household chemicals, cooking fats etc. with care - they can do serious environmental damage otherwise. For advice see www.wiltshire.gov.uk/rubbish-and-recycling