A cover letter is a onepage document that supplements your resume. Date and contact information; Salutation or greeting; Opening paragraph; Middle paragraph(s); Closing paragraph; Letter ending and signature.Describe your unique skills, attributes, and what you can offer the employer. Use a font size that makes sense. 12 point is fine if you need to fill up space. Use good quality stationery, preferably the same as your resume. Explains gaps in your resume. I'm going to share with you the three part structure to create a bulletproof cover letter that gets you more interviews. I mailed a resume and cover letter to you on July 20. It should include the position you are applying to, how you found the position, and introduce your fit for the position.