Following Harold’s excellent example, I have put everything you need to know to be an environmentally responsible citizen on a 4×6 card. (I wish environmental policy could be similarly condensed, but it’s complicated; “Carbon charge!” goes a long way, though.) 
Walk, bike, e-communicate, and public transit when you can. Drive a high-mpg car, and keep it as long as possible.
Live close to work and shopping
Eat less meat.
Garden appropriately for your climate. Less turf.Â
Drink tap water, not bottled. Showers, not baths.
Insulate, weatherstrip, switch to CFL and (better) LED light bulbs. Then, focus on (i) in winter, energy that goes out through the walls of your house: lower the thermostat and put on a sweater, don’t obsess about lights and appliances because they just offset your heating system;  (ii) in summer, what comes in and has to be taken out by air conditioning: shades, awnings, whole-house fan; raise the thermostat and wear shorts; turn off lights and minimize cooking and appliance use.
Reuse, repair, retain; have less stuff and less house (share walls, consider an apartment), but have a recent refrigerator, and a dishwasher that you load full before running.
Vote and agitate. For a carbon charge, walkable/bikeable/transit land use, high gasoline taxes and low fares; against free parking.
Author: Michael O'Hare
Professor of Public Policy at the Goldman School of Public Policy, University of California, Berkeley, Michael O'Hare was raised in New York City and trained at Harvard as an architect and structural engineer. Diverted from an honest career designing buildings by the offer of a job in which he could think about anything he wanted to and spend his time with very smart and curious young people, he fell among economists and such like, and continues to benefit from their generosity with on-the-job social science training.
He has followed the process and principles of design into "nonphysical environments" such as production processes in organizations, regulation, and information management and published a variety of research in environmental policy, government policy towards the arts, and management, with special interests in energy, facility siting, information and perceptions in public choice and work environments, and policy design. His current research is focused on transportation biofuels and their effects on global land use, food security, and international trade; regulatory policy in the face of scientific uncertainty; and, after a three-decade hiatus, on NIMBY conflicts afflicting high speed rail right-of-way and nuclear waste disposal sites. He is also a regular writer on pedagogy, especially teaching in professional education, and co-edited the "Curriculum and Case Notes" section of the Journal of Policy Analysis and Management.
Between faculty appointments at the MIT Department of Urban Studies and Planning and the John F. Kennedy School of Government at Harvard, he was director of policy analysis at the Massachusetts Executive Office of Environmental Affairs. He has had visiting appointments at Università Bocconi in Milan and the National University of Singapore and teaches regularly in the Goldman School's executive (mid-career) programs.
At GSPP, O'Hare has taught a studio course in Program and Policy Design, Arts and Cultural Policy, Public Management, the pedagogy course for graduate student instructors, Quantitative Methods, Environmental Policy, and the introduction to public policy for its undergraduate minor, which he supervises. Generally, he considers himself the school's resident expert in any subject in which there is no such thing as real expertise (a recent project concerned the governance and design of California county fairs), but is secure in the distinction of being the only faculty member with a metal lathe in his basement and a 4×5 Ebony view camera. At the moment, he would rather be making something with his hands than writing this blurb.
View all posts by Michael O'Hare
Especially: eat less RED meat. Otherwise I tip my ecologist's hat to you.
Best,
D
Have fewer children?
Nothing about: "Have fewer children, preferably zero, certainly no more than one until the global population is substantially smaller".
And THAT, ladies and gentleman, is why we are doomed. Because the details don't matter; what matters is that exponential growth is unsustainable, regardless of what cracks first; but 99% of the population are unwilling to accept this and its consequences.
Far more fun to rail against the guy who takes long showers than the guy with eight kids, regardless of the actual NUMBERS involved.
These are reasonable guidelines, for the most part.
I must quibble with some of your land use ideas though. I think these issues tend to be much more complicated than you can fit on an index card. F.e., the main anti-free parking guy, Prof. Shoup, talks just like a straight neolib economist. No consideration for different income levels and so forth. This makes me not trust him. "Live close to work." My, my, but it sounds so easy. It is the same with rent controls. Sure, you can make a nifty economic argument for why it's counter-productive, and in *theory,* it may even be airtight. Unfortunately, reality is a different story. There is this thing called politics…
So, much of this I agree with, but not the planning parts (especially since cars are getting cleaner…)
I wanted to add, the reason these land use issues upset me so much is that my local government here in LA is famously dysfunctional when it comes to planning. (The LA-based posters here all live on the Westside, afaik, where is it much easier to ignore the problems. Well, unless they try to go downtown.)
We have an anemic system of public campaign finance, low information and apathetic voters, and a completely inadequate City Council structure, and its planning traditions are even worse (it is openly a matter of, each member gets to rule his/her (*1 of 15 is female*…) district). No one at all speaks for ordinary, middle or lower-income voters. The supposed nonpartisanship does not help, imo. Meanwhile, however badly LA has been (un-, non-)planned in the past, most of us ordinary people are stuck in it. Our economy has been sucking wind for years. Oh, and the local press **stink.***
It is basically the Wild West for developers. This city is more or less openly run by the One Percent. Maybe it is different where you live, such that these blythe planning nostrums seem to make sense.
And, I forgot to mention, the state Legislature has taken it upon itself to do local planning now. They helped try to shove a **completely unneeded** downtown stadium down our throats, aided by no less than the local NRDC chapter. (Thanks guys.)
They just forced a ginormous "TOD" near an intersection with **no subway** — unfortunately, I can't recall just now if it's in WeHo or LA — but, no matter, since the citizens don't really get a say anymore anyhow. (Okay, I'm a bit overheated — probably it is just a CEQA exemption to speed up the suits — but why is it the Legislature's job to make local decisions???? Just because our local govt blows giant chunks is no reason to think people farther away will do better). Few of the people who live in that thing, if it's built, will take buses. Just my guess, since the units will be expensive (the only kind getting built these days).
So, I gotta call "Bullsh*t!" on all this "green" planning. Please, please don't drink the Koolaid so fast.
It seems to me that "avoid air travel" should be on the card.