Select the case depending on the age of the person to whom you are writing. A child less than 16 years, decided to contact "you" when communicating with a stranger older rules of etiquette require the use of the pronoun "you". It is quite acceptable to name a boy or a girl by the name without the patronymic, e.g., "I know, Alexander, that you..." or "I decided to write you, Natasha...". To person middle-aged and older first name and patronymic. If the letter of a formal nature and is addressed to that person, regardless of age call him by his name and patronymic.
In the beginning of the letter politely greet the addressee. If the person does not belong to any particular culture, to fit the traditional greeting "Hello", "Hello". Be careful to use adjectives such as "dear", "honey" - in a letter to a stranger they are often inappropriate.
Introduce yourself, give some information about yourself.
Briefly formulate the essence of his letter. Inform the recipient about how you want him to tell us something, something to ask or something to apologize. For example, "I Think you will be interested to know that you have relatives in Belarus" or "Circumstances compel me to address you asking help."
Describe the information you want to convey to the addressee. Try to write concisely, avoid ambiguous phrases and expressions: people don't know, don't know which of you to wait, so it is likely to be misunderstood.
The letter specifically formulate his request or suggestion to the addressee, there was no doubt about what you still want. If you Express a request, accompany it with apologies for the caused inconvenience.
Politely say goodbye. Thank you for attention to your message.
Proofread the letter, make adjustments as necessary.