Use duties as your starting point
IRCC’s NOC guidance tells you to check that the listed main duties match the work you actually performed. A similar job title is a starting point for research, rather than a complete explanation of the job.
Build a comparison worksheet
Write a factual description of your role, the dates and the responsibilities you can document. Record the official NOC page and version you reviewed beside your notes. If something does not match, leave it as a question to investigate rather than rewriting your work history to fit a code.
Keep evidence and scenarios distinct
Label calculator comparisons with the occupation assumption used and the date you checked it. Keep employment documents in private storage. A calculated result does not validate a NOC selection or decide whether the work meets a program’s requirements.