Step 1:
Once you are ready to set up your email signature, log into your Yahoo Mail account using a web browser. At the top right, click on Settings.
Step 2:
On the panel that opens up, click on More Settings at the bottom.
Step 3:
On the left menu, click on Writing email.
Step 4:
In the Signature section, ensure that the signature toggle is enabled for your email address and paste your new signature into the text box provided.
Step 5:
Click the Back to inbox button in the top left corner and then click to compose a new email message. Enjoy your new signature!