Everyone's metadata is different. Even between one's own collections, the metadata can change. The rule of thumb, however, is you must have two things when uploading metadata: a title and the filename of the item being uploaded (at a minimum).
It is key for Rosetta to have metadata attached to the preserved material. What we are looking for is to preserve the metadata with the uploaded items being preserved.
Title is the most important as it names the piece. This needs to be the first column in your metadata file. Any subsequent element is up to the individual editing the metadata file.
The final column needed is the filename. I say "final column" as it should be the last, sequentially, of your columns. This column is necessary later for the naming of files, as well as the mapping of the metadata and ingested item.