When you create an avatar on Yahoo! Avatars, this avatar is automatically displayed in your Yahoo! Mail account on the welcome page. Only you can see your avatar here.
If you don't have an avatar yet, Yahoo! Mail displays a gray avatar silhouette on your welcome page. Click this image, and you are taken to the Yahoo! Avatars site where you can create your own avatar.
To update your avatar from inside Yahoo! Mail, just click the avatar. You'll be taken directly to the Yahoo! Avatars site.
To remove your avatar from Yahoo! Mail, you must delete your avatar.