Setting Up Email Signature in Outlook Web

Create an email signature

Sign in to Outlook on the web.
On the top nav bar, choose Settings > Mail, which opens the Options panel on the left.
In the Options panel, under Mail, choose Layout > Email signature
In the text box, type your signature and use the available formatting options to change its appearance.
Note: Inserting an image file (in a .gif or .jpg format for example) for your signature isn't supported, but you can copy an image from a webpage and paste it into the signature box.
If you want your signature to display at the bottom of all outgoing email messages, including replies and forwards, select the Automatically include my signature on new messages I compose check box. - If you don’t select this option, you can manually add your signature to a selected message.
Select Save when you're done