You can edit your personal set of Email notifications in the System notifications tab of the Settings menu.
In this page you can decide which notifications you want to send and to whom you are sending them, either customer or agent.
For example you can decide to inform your agent if the ticket is edited. To enable this notification, look for the option a ticket is edited and tick the checkbox under the column to agent.
If you want to edit and personalize the template of each mail you can simply click the View template button: a pop up window will show you the actual text of the email and you can configure by hitting the green Edit button in the bottom right.
This will bring you directly to the Email template tab of the Template section of the Settings menu, and you’ll be free to change everything about the text.
Hit confirm when you finished.