Jobs should be listed in reverse chronological order (that is, your most recent job is listed first.)
Listing must include name of company, city and state. Do not list street addresses, supervisors, telephone numbers or reason for leaving.
Include your job title so the employer has an idea of the work you performed. If you didn't have an official title, choose one that best describes what you actually did at this job.
Dates of employment are required. Be sure to include month (or term) and year, i.e., Fall 2011 or June 2010-present.
Typically job duties are not included here unless they are highly relevant to your objective. Even then do not include duties which are implied by your job title or alluded to in the Summary of Qualifications or Profile section. However, job accomplishments SHOULD be listed as bullet statements under each position as applicable. These likely came to light when you were developing your summary of qualifications section.
What jobs should I include?
There is no rule about which jobs you must include. Use your discretion and include everything needed for the employer to make the decision to contact you for an interview. You might list every job you've ever held or you might just list your last 3 positions. Note that on a job application you must include your entire work history (or as requested on the application.)
Another approach might be to only include the relevant positions you've had and name the section Related Experience or Relevant Work History or something similar.
If your most relevant experience, say an internship or other employment is not your most current position, you might consider creating a separate section titled something like "Related Experience" or "Internships" where you will be able to isolate and highlight this experience. You'd then follow with the unrelated (but still valuable) experience in a Work History section.