My method is, I open Notepad (actually Textpad), and start by outlining my points. I find, often, that the outline is suffient to get the idea across. I change the outline point to a grammatically-correct sentence or two, look around the net for a few links to back my points, check the format and put it through Word for a grammar- and spell-check, and post.
The whole process often takes less than an hour. This one was done in 75 minutes. The alteration of outline points to proper sentences ensures the brevity that I treasure.
I know how to do it, but my planned/scheduled writing time is dedicated to my next novel. Outside of that, the only writing I’m doing now is what happens spontaneously.