Top menu >> Setup >> Basic fields
You have the option to add fields to the following pages: Agencies, Reps, Customers, Customer locations, Account, Staff and Suppliers. This feature is used to keep track of information that is not part of the default fields that are available on these pages.
From the Setup page >> click Basic fields.
Select the page you want to add the field to (1): Agencies, Reps, Customers, Customer locations, Account, Staff or Suppliers.
Drag and drop the field in the target area which will turn yellow when ready to drop (2)
Name the field and click Finish.