This letter is the first example of your writing skills and how you present yourself. Be careful to check for grammatical and typographical errors. Keep your letter short to insure holding the reader's interest. Three to five paragraphs is sufficient. Also, stay away from lengthy paragraphs.
Short paragraphs are more effective.
The body of your letter should include facts about your past experience in addition to stressing your accomplishments. Appeal, in your letter, to the self-interest of the person to whom you are writing. Propose a mutually beneficial association with that employer. The opening paragraph needs to arouse the reader's interest in a business-like manner. Asking a question.