Cover letters are one-page documents consisting of at least three parts. The purpose of a cover letter is to make a compelling case for yourself as a candidate for a particular job, and it complements what's in your resume.In this guide, we will discuss the importance of a cover letter and provide you with tips and tricks to help you craft an effective one. Study this sample cover letter and explore the dropdowns below to learn how to craft a quality document. Improve your cover letter to get a better shot at an interview. Attend a workshop, view a template or example, or get your cover letter reviewed. Always write a cover letter from scratch. Explain your past positions, experiences, and skill set. But, be careful because the second paragraph should not be a reiteration of what is on your resume. Explain your past positions, experiences, and skill set.