Step 1:
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.
Step 2:
Copy the signature to your clipboard.
Step 3:
Open the Yahoo Mail App on your Android device. In the top left, press the menu button, then press Settings.
Step 4:
In the Settings menu, scroll down until you see Signatures and go into it.
Step 5:
Remove any text that is currently in the signature text area. Press and hold over the email signature text area until a pop up box comes up and then paste the new signature.
Step 6:
Your new email signature is now installed! Test it out by composing a new email to make sure it looks correct.