I found I got a lot "better" at communicating just by toning down my geekiness. Not by changing in the content of what I say, just by changing my bedside manner. Instead of saying, "and this part is neat," I joke about how much the computer sucks and how annoying it is. When I do that, people trust that what I'm telling them is actually helpful and relevant to their usage of the machine. Before, they would ignore most of what I said. They tried to filter out what they assumed was gratuitous geekery so they could get to the "payoff" where I told them how to do what they need to do. Since I wasn't actually wasting their time with extraneous information, they missed most of what they needed to know to understand what I was telling them. It's really hard to talk to people when they assume the proper way to understand you is to hear about 10% of what you're saying.

When I pretend to hate computers as much as they do, they actually listen to everything I say, and voila, they understand a whole hell of a lot better.