Promet Source: A Roadmap for Manual Web Accessibility Testing

The process of auditing a website for ADA accessibility compliance falls into two essential categories: automated and manual. The automated part of the process is relatively straightforward. It’s simply a matter of leveraging the right tools for diagnosing non compliance with WCAG 2.1. The next and indispensable step tends to be open-ended and undefined. 
Where to begin? 
What’s the scope of the process?