ISO has published a companion handbook to ISO 13485:2016, Medical devices-Quality management systems - Requirements for regulatory purposes. From AAMI:
It provides users with practical guidance and accurate interpretation of the requirements specified in the standard. It offers device manufacturers step-by-step guidance applicable to the all stages of a medical device's life cycle from gathering customer requirements to design and through to post-market surveillance of devices. This go-to resource is ideal for regulatory, compliance, quality management professionals who are committed to implementing and maintaining a quality management system that is effective and meets applicable regulatory requirements.