The Interest Register is found under People on the main navigation bar.
Depending on your country, this may be known as a Declaration of Interests or Conflict of Interests.
You can add an interest on your People page from the top right of your Interest Register tab.
To edit an interest click on the three dots on the right hand side.
You can edit the:
The Name of the organisation
The Nature of the Interest (this expands so that you can add as much relevant information as needed)
Change the Notification Date
Add (if applicable) an End Date