You may want to become an advocate for suffering Christians around the world. Remembering those in prison as if you were their fellow prisoners, and those who are mistreated as if you yourself were suffering. Start by checking out the informative resources available from Open Doors. Each newspaper has its own guidelines for submitting letters. But generally, letters to the editor should be no more than 200 to 250 words, and should address one single issue.
Editors especially enjoy feedback on coverage of stories which have appeared in their papers.
You might want to write to thank them for their coverage of a particular issue or event. It is also appropriate to write a letter of criticism if editors have neglected to adequately cover an issue. A word of caution, however. DO NOT criticize unless you are absolutely sure of what you're writing about. It would be embarrassing to find that there were more than 300 articles within the last year on a particular issue which you thought deserved more coverage.