Open the PDF in a PDF editor that supports form fields
Enable form creation or form editing mode
Add text fields for typed responses
Add checkboxes for yes/no options
Add radio buttons for single-choice selections
Add dropdown menus for list selections
Add date fields if needed
Add signature fields if needed
Set field properties such as name, size, and required status
Align and format the fields to match the document
Save the PDF as a fillable form
Test the PDF by opening it in a PDF reader and entering data