When not in use, an antimension is folded in thirds both vertically and horizontally and stored underneath the Gospel book on the altar. During the Divine Liturgy, it is unfolded part-way, then fully, and the vessels holding the Eucharistic bread and wine are placed on the antimension. It is then re-folded at the conclusion of the Liturgy.
An antimension need not contain any special imagery, and some early antimensia were very minimalist in their designs. Traditionally, however, an antimension will have symbolic images of the Evangelists in the corners, and typically (though not always) some variant of the Deposition in the Tomb as a central image.