A rhetoric for authoring hypermedia products (my summary):
1. Links must be to non-trivial materials
2. Provide navigation tools, both organizing overviews and maps of current pathway:
   • Graphic concept map
   • Flow chart
   • Timeline
   • Natural objects (labels, parts)
   • Outline
   • Text as its own overview
3. Multiple overviews of same materials
4. Anchor links in a meaningful context
5. Arrival point at link destination must be meaningfully related to where one came from
6. Keep individual documents short

Based on George P. Landow, "The Rhetoric of Hypermedia: Some Rules for Authors," in Hypermedia and Literary Studies, ed. Paul Delany and George Landow (Cambridge, MA: MIT Press, 1991), pp. 81-103.