Probably the easiest way to be greener is simply to start recycling - and that means sorting your paper (cardboard, envelopes etc), glass, tins and your old newspapers and magazines. You can use your green box but personally I am quite fussy about doing my recycling and always take what I've got to a supermarket car park and put it all in their recycling bins. If you sort it all out into different bags before you leave home it's much quicker once you get to there to get rid of it. You can also make things even easier by getting specific bags for recycling and putting them in your kitchen; either just separate them as you go into plastic bags or get some made especially for this purpose - I saw some at B & Q and Penzance. I would link to the online page for these bags, which I think are brilliant, but after having scoured Google I cannot find them! So my advice is to go into the shop and have a look, I expect they will be stacked near the bin bags.
Don't forget to actually recycle your plastic bags either; I'm only human and yes I do sometimes forget to take my lovely Co-op cloth bag with me when I go out (try and keep it in your handbag or pocket if you can though), in which case I will get a plastic carrier bag, however, I always reuse or recycle the bag. I have included this brilliant link to Recycle for Cornwall, as it gives a lot more advice and information than I could ever possibly give; it also has a page on home composting, which I do religiously, and will be covering in my next post!
Recycle for Cornwall