About writing better - since I'm sort of a professional writer (not in English though :)), here are a few concepts that may help - they are not really scientific as far as I can tell, but many writers recommend them, and in my experience, they are quite useful.
First, the distinction between the editor's brain and the creative brain.
The creative brain is what we use during "stream of consciousness writing". We just "get it down", and once in a flow, may even tap into some sort of "higher source", or great inspiration, however you want to call it. The words, concepts, and ideas start coming and flowing. It is important to switch off the editor's brain during that process so that we don't obsess about grammar, spelling, research etc., which may interrupt the flow. The result is what some writers call the "vomit draft". Just get it out.
The "editor's brain", on the other hand, cares for grammar, facts, research, and makes our writing as accessible and clutter-free as possible. Usually, we engage it after the "stream of consciousness" phase. We want to separate these two phases.
Then, there are mainly two different approaches (which of course can be combined and are not always that clear-cut): discipline-driven vs. creative approach.
Discipline-driven: you create a detailed outline of what you want to write about, including subheadlines, a few bullet points and so on. Then, you get into "stream of consciousness" writing and fill it all out, sticking to your outline. If you stumble over something you need to look up, research etc., make a note for later so that you don't interrupt the flow. After you got it down, do the editing, corrections, formatting, fill in the missing research and facts etc. This can be highly effective.
Creative approach: you just start writing and let the ideas flow. The result will probably be less structured and "on point", which you can correct during the editing phase. Usually, the editing will take more time, since you may have to shuffle whole paragraphs around, delete stuff, identify holes you need to fill out etc. On the plus side, you don't restrain your "flow" with a rigid outline, which can produce very interesting results.
So a common approach would be:
[list type=decimal]
[*]Research, read, gather facts
[*]Optional: create an outline
[*]Get into "stream of consciousness writing" and produce the "vomit draft". Hammer it out.
[*]Do the editing, corrections, formatting etc. to make the text as accessible and on point as possible.
[/list]
For a longer forum post, the process would look something like this:
[list type=decimal]
[*]Read the thread to find out what has already been said and to get a detailed picture of the problem, facts presented etc. [Research]
[*]If necessary, use the search function to research more on the topic (both on the forum and on sott, maybe in your (e)books and possibly on Google) [Research]
[*]Optional: create an outline, either by taking notes directly in your post or just by having a clear idea in your mind as to what you want to write/which points you want to convey. Sometimes I do this before the research stage. [Outline]
[*]Type the whole thing in one flow. ["vomit draft"]
[*]Use the preview function to read it again carefully, streamline it, correct grammar/spelling as best as you can, add hyperlinks and formatting, and make it as easy to understand/follow as possible. [Editing]
[/list]
Just a few thoughts on the matter :)