Be scrupulously detailing what you have already accomplished. A resume is a marketing tool - not a career obituary. These accomplishments may not have all come from the place that issued your paycheck. Your work with PPN is a prime example of an opportunity to translate an unpaid position into a concrete qualification or position held. If you were in the military, translate your skills into civilian terms, and avoid the lengthy actual titles you had to carry around in the service.
All resumes contain much of the same kind of information.
What varies is the way it is organized. Leave objectives to your cover letter, and you will get more mileage out of your resume. On the other hand, preparing targeted resumes for a specific objective is always the best policy. Word processors allow so much flexibility in the terms you chose to highlight or omit depending entirely on each situation. Dates are dangerous sometimes.