Set up a signature, i.e. a text snippet that will be appended automatically to any email you send.
Tap the menu symbol in the menu bar.
The menu navigation will appear.
Tap Settings.
Tap Mail Settings.
Tap Signature.
Create a signature, e.g. "Sent with my iPhone" or add your personal or business contact information.
Info:
If you enter a signature text, it is automatically added to every new email you send.
You can also change or remove this text when writing an email. This does not affect the stored signature.
The signature text can be up to 500 characters long.