How to become good assessor for ISO 17025:2017?

As the principle of Auditing the management component of all Quality management systems, including ISO 17025 involves the same approach and techniques, you could benefit form the Internal Auditor training offered by the ISO 9001 Academy. Have a look her for further information https://advisera.com/training/iso-9001-internal-auditor-course. To strengthen your skills with ISO 17025 technical assessments, I suggest refresher self-learning on the purpose of ISO 17025 and its risk-based approach.

The following will provide more information for you on Auditing and ISO 17025:

How to perform an internal audit using ISO 19011 at https://info.advisera.com/free-download/how-to-perform-an-internal-audit-using-iso-19011

ISO 17025 document template: Internal Audit Procedure at https://advisera.com/17025academy/documentation/internal-audit-procedure/

The Five Internal Audit Procedure appendices Internal Audit Program, Internal Audit Checklist, Audit Nonconformity Report, Internal Audit Process Checklist and Internal Audit Report are available separately from the procedure link above; or included in the toolkit at https://advisera.com/17025academy/iso-17025-documentation-toolkit/

Clause-by-clause explanation of ISO 17025:2017 at https://info.advisera.com/17025academy/free-download/clause-by-clause-explanation-of-iso-17025/

The Book - ISO internal audit: A plain English guide at https://advisera.com/books/iso-internal-audit-plain-english-guide/