A page can contain a main text, short notes, a heading, and material squeezed between lines. Starting at the top left and copying everything in visual order may produce a sentence that no historical reader encountered. A simple layout sketch helps you keep separate textual spaces apart.
Use a digital image or permitted reproduction. Draw rectangles for the large blocks, then label them A, B, and C. At this stage, describe position rather than function: “outer margin” is safer than “correction” when you have not read the words.
Test one transition
Choose the end of a line or paragraph. Does the next phrase continue naturally in the same block? Is there a visible reference sign connecting it to a note? Record the connection only when you can explain what supports it.
For an invented practice page, imagine two columns with a short note between them. Keep three transcriptions initially. Combining the note with the left column merely because it is nearby would erase the distinction you need to investigate.
Consult the edition’s layout conventions before deciding how to represent the page in running text. If you cannot establish the order, retain the separate blocks and describe the uncertainty instead of silently arranging them.
The sketch is a working aid, not a reconstruction of the book’s production. Its purpose is modest: another reader should be able to tell which words you saw together and which connections you inferred.