How to develop communication skills?

Good communication skills allow you to paint clear mental pictures with words. The best way to develop those skills is to use them as often as you can. If you pay attention to speakers and writers, generally the longer it takes for them to explain an idea, the less they know about the subject.

Start with a clear understanding of what you intend to say, provide the background needed for the reader/listner to understand your idea and then make your point. Abraham Lincoln's Gettysburg Address is a great example.