When you get an idea for an article, what do you do? I suspect a lot of you will scribble the idea down along with your thoughts on how the article might be structured and what it's content might be. You may well also, like me, write your idea under headings and note down any side bar info, ie, top five tips, etc, that will pop out of the main article. I tend to have a market or two in mind at this stage too, purely so I can get my brain in gear to write in the style and tone/word length/ layout that particular publication favours.
The most important thing, I think, when you get your initial idea is to find your focus, or the angle the article is going to take. It hasn't got to be set in stone at this early stage as the more you think bout the article idea the more off shoots you might get that will change your focus. This is fine as this is how you get several articles from one idea. Like a wheel or a pizza you turn your focus a few degrees until you hit on a different angle.
It can be tempting, however, to try and cram in as many different angles that pop into your head into one article that you can, but this will result in a confused, wishy- washy, all over the place, over stuffed article. One angle/focus per article is generally enough to explore the topic sufficiently. But do write things down associated with that topic as they occur to you. Nothing is ever wasted and you will use your other angles at a later date.
So get your compass out and get finding your angles - but don't lose your focus - act like a photographer and choose the right lens to frame the picture.