An email signature is a block of text automatically added to the end of an email message.
It generally includes the sender's:
Name and surname,
Title and company that they are working at,
Call-to-action landing social media channels or website
Click Settings from the top right.
You will see a "Signature" section. Click it.
Add your signature text to the box (you can also format your email signature by adding an image or by changing the text type),