Again, before you begin your query letter, there are some things you should avoid.  Here are some common mistakes writers make when compiling a query letter.
4 Common Query Mistakes to Avoid

Pitching more than one article. You shouldn’t be pitching more than one article per letter.  If you must, write a separate letter for the other topic.

Writing a query that is longer than one page. Editors skim the letter quickly to see if it interest them, and they’re not likely to read a long query.

Claiming you are the “perfect fit” for …

The standard query letter is split into three major parts: the hook, the body and the conclusion.
The Hook: This is your introduction. It should be something that immediately grabs the editor’s attention, usually consisting of a sentence or two. It should include an important fact or main point that will be the central theme of your article.
Example: “When my friend, reality show vixen Chasey Leone, quit A Roar at Love in March 2007, producer John Syphil gave her a parting gift—an incurable sexually transmitted disease.   But Leone …