To create one from sludge to grouted presentation is time and labor intensive and does require the full use of a ceramic studio & kiln, but "It's worth it!" Now the not so cathartic method involves buying pre-made tiles which you can still hammer into variegated shapes to match your design, however less sweat, less equity. As the fine arts, particularly the studio arts, go I call ceramic mosaics a form of controlled freedom. By controlled freedom I am describing the depth of one's commitment to such a hefty undertaking as well as process limitations.
[You must be registered and logged in to see this image.] by Carl and Sandra Bryant