A collection description is the formalization combined with the Pattern Expression, that documents the used patterns and the rationalizations upon which the collection is based.

The layers are:

Pattern expression

The foundation of the choices for the collection

Write your pattern expression here, it's the rationale behind the collections structure.

Be sure to include the patterns that you use and describe the way relationships affect the pattens.

Collection description

The What

Sum up the elements in the collection here, focus on core descriptive and technical metadata fields.

Workflow

The how

Describe the intended usage of and content addition to this collection, use all available measures that help clarify on the subject. Consider images in addition to text.

Technical

Be concrete and go into detail of things that require it, especially parts of the collection that is complex or of a special nature.

Consider using a drawing to illustrate relations or for instance include code/XML snippets