The document outlines 8 common mistakes to avoid in cover letters: 1) Focusing too much on yourself and not how you can benefit the employer. 2) Including unnecessary details about past jobs. 3) Discussing uncomfortable topics like being fired. 4) Writing overly long cover letters. 5) Simply restating information from your resume. 6) Using trite phrases. 7) Excessively flattering the company. 8) Containing typos or grammatical errors. Employers want cover letters that demonstrate how the applicant can fill their needs and that are concise and error-free.