Honestly, I don't expect everyone to move their own arses (i.e. get involved in activism). How you choose to behave, live your life, and the associations that you make is more important anyway. An ideal is achieved when enough people's behavior falls in line with it. If you're behaving as close to your ideals as you can, then you're already doing your part. Activism only attempts to convince people of an ideal or combat the symptoms of bad behavior.
The only thing I request of non-activists is don't be negative towards people who are actually out trying to do something. If you agree with a movement's ideas, then don't put them down just because you don't understand their methods or pay enough attention to even know what their methods or achievements are.
You don't know how often I hear things like "The environment is important, but all I know about environmental activists are these one or two crazy things the mainstream media spun at me, so I don't like environmental activists" or "I agree with everything the Occupy movement says but what does standing around with a bunch of signs and getting arrested accomplish? I think the movement is stupid and should go away."
That's when I have to take them to task on it. "What the fuck are you doing? Nothing? What do you think they should be doing? You don't know? Ok. Shut up, then. All your negativity is doing is working against the very ideas you claim to support..."