Keep them simple. Make them as visual as possible. Define their distinctive characteristics as they relate to your product/service. Stick posters up around the building of them so that everyone "gets to know them". Keep them on a sharable platform, so that you can have a "front page" for each and then more information about them if someone wants to know more!
Find a way to present them together on one slide, so that people can see how they are different from each other.
Does this help?