To edit the name of a template, go to the Templates section in Signaturit's control panel.
Then, click on the template in your list of templates to enter into the template's details.
Within the template, click on its name at the top right:
This option is very useful for when you send templates from your email or when you duplicate a template.
When you duplicate a template, you will see that an identifying string has been added to the title of the copy so that you can differentiate it from the original.