To add Private note to an Incident, follow the below steps:

1. Click on the Incidence & Maintenance icon on the left side menu bar.
2. Click on the incident in which you wish to post a private note.
3. Enter the update in the text area present at the bottom of the page.
4. Toggle the "Private Note" switch, if you wish to make the update private. Note: A Private note will not be posted to the public status page and it remains an internal team communication.
5. Select the date from the date selector, if the update happened at a specific time.
6. Click on the "Post Private Note" button to update the incident. 

Note: 'Email subscribers' and 'Tweet this' checkboxes will be disabled for private note updates.