How to add a signature in Outlook

On the View tab, select  View Settings. 

Select Accounts > Signatures.

Select  New signature, then give it a distinct name.

In the editing box below the new name, type your signature, then format it with the font, color, and styles to get the appearance you want.

Select Save when you're done.

With your new signature selected from the list above the editing box, go to Select default signatures and choose whether to apply the signature to new messages and to replies and forwards.

Select Save again.