Job seekers often spend countless hours developing their resumes and then treat their cover letters as an afterthought. This can be a critical mistake; the cover letter can help your resume get noticed.

Think of the cover letter as your resume's cheerleading section. To make the best impression, follow these etiquette rules:

Say No to the Cover Letter Cop-Out

The first rule of cover letter etiquette is to send a cover letter -- always. It doesn't matter if the hiring manager didn't ask for it or you're too busy to write one. It's proper business etiquette to accompany a resume with a cover letter, and it gives you the opportunity to help sell yourself for the position.

Be Concise

Busy hiring managers don't have time to wade through letters that could pass for dissertations. Get to the point as expeditiously as possible, and break any paragraphs seven lines or longer into short, easily digestible ones.

When emailing your cover letter, brevity is even more important. The nature of email calls for concise communication, in part because it's harder to read on screen than on paper. However, don't fall prey to the one-line cover letter that some job seekers try to pass off. It goes something like this: "Please see attached resume, and thank you for your time and consideration." You should be able to write a convincing cover letter in a few brief paragraphs.

Keep It Professional But Friendly

While a resume is generally a formal document, cover letters give you a chance to reveal your personality. Not only do you want to show that you're a good fit for the position, but you also want the reader to like you. Appropriate use of humor, combined with a friendly and professional tone, can help endear you to the hiring manager.

Get Personal

Whenever possible, address your letter to a specific person. If a job posting doesn't include a person's name, do some research to find out who the correct person is. Try calling the employer (but do respect ads that state "no phone calls"), and ask a receptionist for the hiring manager's name. Keep the salutation professional by using "Dear Mr. Jones," not "Dear Jim."

Focus on the Employer's Needs

If every other sentence of your letter begins with "I" or "my," you need to change the focus. Research the employer and find out what types of problems managers there are facing, qualities they look for in employees and their future goals. Then use your letter to prove that you are the answer to their problems. The most compelling letters demonstrate what you can do for the employer, not what the employer can do for you.

Be Original

Your cover letter will stand out if you employ some creativity. For example, you could include a brief summary of your toughest sale or most challenging project.

You could incorporate excerpts of performance reviews to highlight your record of success. Or, you could create two columns in your letter to demonstrate precisely how you meet the employer's requirements:

Proofread

Cover letters should be free of errors, so thoroughly proofread them before sending. If proofreading is not your strong suit, get help from someone with meticulous proofreading skills. If you're customizing a cover letter that you use for many positions, remove any placeholders; this will prevent embarrassing errors such as "I would be delighted to be your next ." And one last tip: whatever you do, please spell the hiring manager's name correctly.

Following cover letter etiquette can be time intensive, but the reward is worth it: More calls for interviews and a greater chance of securing a new position.