The best way to conduct an effective gap analysis for a company implementing ISO 9001:2015 is to compare what your company already does with the requirements of the standard. You can use a gap analysis tool specific to ISO 9001:2015 or the standard itself for a thorough analysis. Have someone knowledgeable in your operations assess each requirement and document what you already do that addresses each requirement. This will help you identify the gaps that need to be addressed to achieve full compliance with ISO 9001:2015.