Don't Make Me Think is the title of an excellent book on building websites by Steve Krug. If you are building any sites, you need this book. But even if you don't, it's worth a look, because it's really about how people respond to processes.
So often we make designs/processes based on some sort of logic, but forget to test them out with people. Krug stresses, over and over, that everything in a site needs testing. I believe this is true in community work, web-stuff, application design, windowing systems, game design, documentation, and on and on.
One of the points that I noticed, although he didn't stress it, is that small changes need testing, because when you emphasize one thing, even things you didn't touch are de-emphasized. So lots of small tests, quite frequently. Don't make a big deal of it; just grab someone, let them test your site/app/process/interface/form/design, and then fix what is obviously wrong.
Lather, rinse, repeat.