Promoting your photo contest via your website, email lists, Facebook, Instagram, and Twitter pages is the one of the easiest ways to get the word out about the contest. Encourage your staff, volunteers, and friends to talk about the photo contest on their Facebook and Twitter pages as well!
You can also promote your contest using donated or purchased newspaper ads and radio spots. You can promote your contest in your organization's newsletter, by placing promotional posters around your community or using any other creative ideas you come up with.
Don't forget to involve any sponsors you might have in getting the word out about your contest!