Use the workflow as a pre-launch and change-review checklist: identify the processing, confirm the lawful basis, check special category or criminal-offence data, confirm notices, evidence, retention, security, and review triggers, then assign ownership and a next review date.
First confirm scope. The UK GDPR can apply to processing in the context of a UK establishment and to an organisation outside the UK that offers goods or services to, or monitors the behaviour of, people in the UK. Then identify the controller, any joint controllers, and each processor for the actual decisions and operations. The DPA 2018 supplies UK-specific conditions, restrictions, and exemptions; it is not a replacement for the UK GDPR.
A checklist item passes only when the live processing matches the recorded decision and the evidence can be inspected. Use 'not applicable' only with a reason and cited condition; use 'open' where facts, ownership, or remediation are missing. Distinguish binding duties from ICO guidance, optional certification, internal policy, and Sorena's suggested evidence fields.