If so, scroll down to the bottom, and choose the option to view the full menu. At first, you may see the Quick Settings menu. Click the cog icon on the right-hand side of the toolbar, and select Settings. Resize the file beforehand, as the image will appear exactly the same way in the signature.
Now, you should see several input fields, allowing you to edit your email details.
How to add a logo to your yahoo signature If you like the finished signature, scroll to the bottom of the page to save the changes.
Open the Settings menu by clicking the cog icon in the upper right corner.