The first step in making a PDF document accessible is to understand what types of issues may exist in the document. When a PDF file is opened in Adobe Acrobat Pro DC, briefly analyze the document and note its characteristics. Does the document have:
Text, links, graphics or a mixture of elements
Headings and/or lists
Mathematical formulas, subscripts, superscripts, or other font attributes
Annotations such as comments, revision marks, etc.
Multiple columns of information
Complex layouts and articles that span different pages
The greater number of document features and complex layouts, the more time it may require to make the document accessible.