A “good” bibliographic record allows any patron in any library to quickly and easily find accurate information about that item. A good record is accurate and complete. You should pay particular attention to these fields.
If you are not sure about an entry in a particular fixed field, right-click on the field. Available choices appear:
You can find a lot more information on fixed fields and their possible values at OCLC Fixed Field
These are minimum standards. Better records have notes, subjects and series information. If the record you are looking at is not up to these standards, it should be edited or overlaid with a better record.
For more extensive information on fields, subfields and what should be in them see OCLC Bibliographic Formats and Standards