Becoming an ISO auditor with different standards

Answer:

I would recommend you attend a course about each ISO standard or perhaps integration of ISO standards. An auditor must be knowledgeable about the audit criteria. Also, I would recommend you attend a course on internal audits. Then, you should start performing internal audits and gain experience.

The following material will provide you information about internal audits:

free online training ISO 9001:2015 Foundations Course - https://advisera.com/training/iso-9001-foundations-course/
ISO 9001:2015 Lead Auditor Course - https://advisera.com/training/iso-9001-lead-auditor-course/
book – Discover ISO 9001:2015 Through Practical Examples - https://advisera.com/books/discover-iso-9001-2015-through-practical-examples/