You go to yahoo homepage then on your right handside their will be a sign that says " sign in " underneath it will say sign up click on it and follow the instructions
kiki@yahoo
Click 'Sign in' on the Homepage.
Yahoo and Google
No, you must sign up with Yahoo to be able to post or answer a question on Yahoo Answers.
The sign in button for Yahoo email is used to enable a user to access their email securely once they have provided their correct user ID and password. The sign in button for Yahoo email is located under the User ID and Password fields on the Yahoo sign in page.
One can sign up for the BT Yahoo Mail on the official page of BT Yahoo Mail on the right hand side. One can also find a tutorial on how to sign up at BT Customer help section of the same website.
Sign up for one
In Yahoo
no
Through yahoo setting >Profile Information>Sign-In-Security, you can update your yahoo account.
If the 'IM' You mean is by Yahoo Inc. You should just be able to sign in with your Yahoo ID Username & Password.