A lot of these things we've been doing for some time, so we don't really consciously think about it anymore:
Reuse: anything we're finished with, we try to find a different use for. If we don't want it., we offer it to neighbors or friends to see if they can use it. If that doesn't pan out, we either put it on the front lawn with a 'Free' sign on it (if it's furniture or something of that nature), or donate it to a charity (old clothing, books, etc.). If it's just plain worn out and not usable by anyone, we try to recycle as much of it as possible.
Reduce: we try not to go too heavy on the "Ah, just buy another one" or "Buy extras" mentality. We also try to reduce the amounts of various things we use on a regular basis. For shopping purposes, we have reusable cloth grocery bags as well as plastic grocery bins to reduce the amount of plastic and paper bags we get.
Recycle: our city has a pretty decent recycle program, so all glass, paper, cardboard, plastic (even plastic grocery bags), etc. is recycled. We recycle everything we can.
We're also setting up a compost in our back yard, so that will significantly reduce the amount of waste that goes into the garbage can. When our lightbulbs burn out we replace them with CFBs (although I know there's a concern with them as well).
Any hazardous materials (paint, chemicals, or computer/electronics components that don't get reused) we take to the local disposal site to get rid of them properly.
On a side note re cars: we've been driving the same van for 10 years. That all sound well and good, but the key here is maintenance. If you don't keep your vehicle(s) maintained, driving an old one can be more harmful to the environment than getting a new one (in fact, the current technology makes many new vehicles a better option environmentally than driving an old one).
*editt* Oh, I should point out that this isn't all motivated my an altruistic concern for the environment or some hippie agenda. This is mostly motivated by money. Although being good for the environment is part of the motivation, doing what we do saves us money.
Post edited April 23, 2009 by Coelocanth