Signature is a custom text which appears at the end of the email message. Signature is used to provide your Name, Address, Company Name, Email Address, Website URL to the receiver. Example: If you will set Signature as your name then every time you will send an email message to anyone, your name will be automatically appears at the end of the email message to receiver.
To setup a custom signature for your customize email that you have created on your domain name, you need to follow the below mentioned steps:
Login to your custom email account
that you have created on your domain name. You can login to your custom email using the URL: webmail.yourdomain.com
Click on "toggle"
button at the top right side.
Click on "Settings"
Click on "Signature"
link under Mail
Click on "Add New Signature"