The following steps outline the detailed labor involved to create the illuminations of one page of a manuscript:
The illumination and decoration was normally planned at the inception of the work, and space reserved for it. However normally the text was written before illumination began. In the Early Medieval period the text and illumination were often done by the same people, normally monks, but by the High Middle Ages the roles were typically separated, except for routine initials and flourishes, and by at least the 14th century there were secular workshops producing manuscripts, and by the beginning of the 15th century these were producing most of the best work, and were commissioned even by monasteries. When the text was complete, the illustrator set to work. Complex designs were planned out beforehand, probably on wax tablets, the sketch pad of the era. The design was then traced or drawn onto the vellum (possibly with the aid of pinpricks or other markings, as in the case of the Lindisfarne Gospels). Many incomplete manuscripts survive from most periods, giving us a good idea of working methods.
At all times, most manuscripts did not have images in them. In the early Middle Ages, manuscripts tend to either be display books with very full illumination, or manuscripts for study with at most a few decorated initials and flourishes. By the Romanesque period many more manuscripts had decorated or historiated initials, and manuscripts essentially for study often contained some images, often not in color. This trend intensified in the Gothic period, when most manuscripts had at least decorative flourishes in places, and a much larger proportion had images of some sort. Display books of the Gothic period in particular had very elaborate decorated borders of foliate patterns, often with small drolleries. A Gothic page might contain several areas and types of decoration: a miniature in a frame, a historiated initial beginning a passage of text, and a border with drolleries. Often different artists worked on the different parts of the decoration.
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