Find the appropriate market for your work. Inappropriate submissions are easily avoided with research. "The Writer's Market" is a good resource for finding which magazines publish the type of article you wish to write. Also check the submission guidelines at the magazine's website. Always read a copy of the magazine before you submit your query.
Write a query letter to the editor about your article idea. Make sure the letter is to the point. Tell exactly what the article you are proposing is about. Also, state clearly your qualifications for writing the article. These should be approximately one paragraph each.
Particularize your query letter to the publication. Send the letter to a specific editor, and explain why your article is right for the magazine.
Keep the letter to one page.
Include clips of previously published articles. Many editors prefer to work with previously published writers. Your clips give the editor a sample of your writing style and your ability to carry out a project.
Include a self-addressed, stamped envelope with your letter if you are sending your query by postal mail. Many magazines still do not wish to receive e-mail queries and will not respond to you by e-mail. Check the writer's guidelines for the policy of the magazine you are submitting to.