I have worked on numerous process documentation projects under general needs and ITIL-oriented frameworks.
Here's a GDPR compliance procedure written using simplified BPMN:
This is a major incident management procedure:
This is a written 'One Page Guide' (two sides of A4 paper maximum; one page shown here) which describe a procedure. The document is designed to be easy to read under live working conditions and the tick boxes enable procedure steps to be confirmed as they are completed:
