Email the signature to yourself and open the shared signature link on your phone.
If you’ve received a shared signature link, simply open it.
Copy the signature to your clipboard.
Open the Yahoo Mail App on your iPhone or iPad. In the top left, press the menu button, then press Settings.
In the Settings menu, scroll down until you see Signature and go into it.
Ensure that the Signature toggle button is set to “ON”. Remove any text that is currently in the signature text area, such as “Sent from my iPhone”. Press and hold over the email signature text area until a pop up box comes up and then paste the new signature.
Important: Once you have pasted the signature into the box, shake the phone until the popup window below shows up and choose “Undo”.
Your new email signature is now installed! Test it out by composing a new email to make sure it looks correct.