Most important, the resume should be an effective sales tool for the particular job you are pursuing. The resume is not an application form. The most impressive information about you or what qualifies you most for the job should be at the job title of the position you are pursing, as well as a summary or qualifications statement.
In the body of the resume, use action verbs in the present tense emphasizing skills and accomplishments and the nature and scope of what you have done. Do not put your dates in the margin. They are not what to emphasize.
You can include them after the city and state where the company is located. For resumes that will be scanned into a computerized applicant retrieval system, commonly used in larger companies, you should not underline or use fancy graphics, colored paper, or elaborate fonts. Use terms and jargon often used in your field and a resume format that is commonly used in your field.
Readability is the most important quality of an effective resume. A resume should be formatted in such a way that it invites a prospective employer to read on, and the content should be itemized as bullets, each item leading off with a dynamic verb that is specific and action oriented so that at a glance, within three seconds, the employer will have an immediate sense of what you have done and what you know. If the resume is readable in these two areas, the employer will be motivated to take a closer look.
It is virtually important that the resume speak to an employer's needs, not the job seeker's. Employers are not usually interested in the fact that you are looking for a challenge or the next step in your career. Instead they want to know how you can help them solve their problem. After all, if they didn't have a problem they would not be hiring. So find out what they are looking for as best you can by doing your research, and give examples by accomplishments through out your resume that demonstrate that you are the best person for their organization.