There are many ways to create a sustainable city. One of the easiest ways is to switch to LED bulbs, this can help reduce your need of electricity and is very easy to do. Other ways include using electric cars, installing solar panels, and even creating a more walkable city atmosphere. This might be difficult for a whole city to do, however there are other things that people can do individually as well, such as throwing away less food, composting, and eating a more plant based diet. You might not live somewhere where it is easy to walk places to limit your CO2 emissions, but easy things like switching your light bulbs to LED, helps create a difference, and potentially could help lead to a sustainable city.

I think that this makes a lot of sense, and that you show a lot of really good solutions. I really like the fact that you included the part about eating a "plant based diet." I think that makes a lot of sense, and it's an easy thing for people to change in their everyday lives. Maybe you could have expanded on the "walkable city atmosphere" a little bit more, but other than that I think this makes really good points.