Make an outline that includes the details you need to include in your character reference letter. Jot down the person's name, address, personality traits, how long you have known him and in what capacity.
Find out who to address the letter to. Begin with the word "Dear," followed by the person's name. If you are unsure who to address it to, use the phrase "To Whom It May Concern."
Introduce yourself and indicate why you are qualified to write a character reference for the person.
Refer to your outline to build the body of your letter. Remember that when you start a new idea, you should start a new paragraph. One paragraph could be about the parent's basic personality, the next could talk about how she interacts with children. Be honest in your assessment. Offer anecdotes and examples, if possible.
Offer an endorsement in your concluding paragraph and relate it back to your opening statement. For instance you could say, "Since I have had the opportunity to watch Steve Cummings at close quarters for an extended period of time, I have no hesitation in giving him a very high recommendation."
Leave your letter of recommendation for a day or so, if possible, and then review it. Read it to yourself. Correct any grammatical or spelling errors. Then write or print a final copy of your character reference letter and sign it.