Sometimes translating the unpaid experiences can seem difficult. Unpaid experiences at any level can count toward your next goal. One approach used by many people is to add a section called "Community Service" or "Volunteer Work." You list the highlights of volunteering here to show that you have interests outside of your regular employment. This is certainly better than ignoring volunteer experience on your resumé but it is not the best way to highlight what you have learned as a volunteer.
Even if you were not paid a salary and did not consider the volunteering as employment, it certainly was productive work and should count as experience. The key is to translate what you gained from the volunteer activity into the language of the paid work world.
It's an adjective and alone does not convey the work that you accomplished. If you did tutoring, use the title "Tutor." If you coordinated a project, identify your work accurately as "Project Coordinator." The fact that you filled this position in an unpaid capacity is part of your description of the work.
Highlight the skills that you learned and demonstrated. What would be important to the work world about what you did? For example, did you raise $100,000? Did you manage a budget or accomplish goals on schedule? Did you supervise? Even if you supervised other volunteers, your success required the ability to be a motivating leader.
Did you have the chance to practice public speaking? Write reports, news releases, newsletters? Did you plan projects, coordinate committees, or train others to do the work? Such skills are applicable to just about any setting.
You do not need to say these were done as a volunteer. Be honest about your experience just like you would with a paid position. Don't overstate what you did but also be sure to give yourself the credit you deserve. And, don't apologize about giving space on your resumé to volunteering. The whole goal of a resumé is to get you an interview.
If you are serious about building a career based on volunteer work, you will need to develop a portfolio that documents your service and supports that you have the skills and experience needed for the job you are seeking. It should contain a job description including title of the position, duties and responsibilities, skills utilized, dates of service, number of hours contributed, and training received. Also include a letter from your volunteer supervisor with a brief evaluation of your performance and overall contribution to the organization. Also maintain copies of any letters of commendation, awards, or newspaper articles that you receive.