Firstly, open a new tab and sign in to https://outlook.office.com/mail/ 

  1. Once signed in, select the settings cog in the top right of your window.
  2. Please click on "Account" then "Signatures"
  3. Please select "New Signature' and then enter a name for it.
  4. Click into the white text box, select the attach image button. Browse to the location of your saved signature - You cannot drag and drop, this feature is not supported.
  5. Now click the save button below. Once saved, please select the default signature from the drop-down list & save the changes once complete.
  6. Providing you have clicked save the changes, your signature should have now changed.