Find an organization to volunteer your time that works with issues that are important to you. 

Figure out what skills you possess that will be beneficial to the organization before you volunteer so that you can suggest ways to help.

Find a volunteer activity that will help you achieve your goals in other aspects of life.

Do not over schedule yourself.  Leave time for your job, family, friends and self.

Be aware that many non profit organizations will require an interview before accepting your services because they need to be sure that you have the necessary skills and are committed to doing the work.

Get everyone you know involved.  Volunteering can be a great bonding experience with your friends as well.

Look into virtual volunteering. 

Think beyond the normal hospitals and churches volunteer activities.  Schools, homeless shelters, soup kitchens, drug rehabilitation centers, international organizations and prisons are among the many other charitable organizations that need volunteers to help them with their jobs.

Look for a volunteering opportunity that will permit you to learn something new, maybe even something that will help you in your career or job.

Be enthusiastic and personable.  If you approach your volunteering as a duty, you will not enjoy the work and neither will the people who you are helping.  So enjoy yourself and allow them to enjoy you.