If you simply ensure the TITLE and the opening paragraph contain popular "keyword phrases" that people in your niche might be searching for on the Internet... then you have done 90% of the work.
Always submit your articles to Ezinearticles FIRST.
Since they are the "Google" of the article directories, it's very important to submit to them first.
Here's why....let's say for example you submit your articles to other directories before you submit to Ezinearticles.
What happens is when your articles go into 'pending review' at Ezinearticles they'll run a check to make sure that you've submitted original content.
The problem arises when they come across a duplicate copy of the same article at one or more of the other directories. If that happens, in most cases your article will not be published.
Write a keyword rich title - with a solution.
Make up a unique title and search for the title in quotes at Google and if the results are not in the millions -- I always aim for under 40,000 - then you might have a very good chance at making the first page on a Search Engine Results Page. A 4 or 5 word keyword works (known as long tail).
Really use your resource box.
Remember the WHOLE point of your article -- is to get a reader to click through to your site.
You put your details at the end of the article -- in the area known as the resource box.
It's here that you have to SIZZLE! Really sell your site -- even better -- offer a solution to a problem. If you have a FREE gift -- shout about it here! This is your free advert -- use it wisely and strongly.