You can create an email signature via your RoundCube mail client so that you do not have to type it every time you are writing an email.

1. Log in to your Webmail (RoundCube mail client). You can achieve this by using the link mydomain.com/webmail.

2. Navigate to Settings.

3. Next click on the Identities section.

4. Then click on the email and the email signature will be displayed on the bottom for you to fill your desired signature.

5. Once click Save.

That is all. You can now send your emails freely and the signature will always be there by default.