I can think of three ways people can be more eco-friendly in Japan.
The first would be a reduction in their use of plastic bags. In my country, the U.K., the government passed a law to make shops and supermarkets stop providing free plastic bags. Everyone has to bring their own bag or pay a small amount of money, around \10, for a plastic bag. I think this would be a good rule to implement in Japan, too. In Japan, part of the exemplary service provided in stores is to give shoppers plastic bags. Reducing plastic usage would be a big step forward in being more eco-friendly.
The second would be for construction companies to build well-insulated buildings. Most old buildings and many new ones are built based on the old idea that air should circulate through a house during summer to keep it cooler and prevent mold. But modern construction techniques, air conditioning and humidity control mean that it is far more energy-efficient to use good insulation and keep the air and temperature conditions more stable inside a house.
The last is for people to carry chopsticks that can be used at restaurants. Free disposable chopsticks are very convenient and widely-used in low-cost restaurants, but when you imagine their use not only by millions of people across Japan but in many other countries where chopsticks are popular, the number of trees cut down for the wood to make chopsticks is immense. Of course, the same can be said for plastic knives and forks in Western countries. If more people carried cutlery with them, there would be far less waste.
All these ideas can be undertaken by individuals. We can ask in stores not to be given plastic bags and use our own instead. If we are having a home constructed, we can request that good insulation and modern heat control technology be used. We can carry chopsticks with us and make use of them when we eat at restaurants that offer disposable ones. However, without government intervention, the impact of these actions will be minimal.
implement (v) ? to put a decision, plan or agreement into effect
exemplary (adj.) - very good and suitable to be copied by other people
circulate (v) ? to move continuously or freely through an area