Walk to local shops to do my shopping in most cases rather than driving to bigger supermarkets. That saves me on petrol which over that last few years has doubled in per litre cost.
I also find buying bulk from these smaller local shops saves me money in the long run then buying small items from super markets branded products.
e.g. rather than buying a bag with say 10 large potatoes, i'd buy a big 10-15KG bag. That saves me money.