You can sign in to www.Yahoo.com website by using the ‘Sign in’ link. The log in page will be displayed on the screen. You will be able to type your Yahoo username in the ‘Username’ field and type your Yahoo password in the ‘Password’ field. Then, click on the ‘Sign in’ button to access your Yahoo webmail account. You could also sign in to Yahoo website by either using your Facebook account or your Google account. You will be able to click on the ‘Facebook’ button or the ‘Google’ button in order to sign in to Yahoo using that account.