We start to login at the Portal Home. This is the Login Page for the Client Area of WHMCS. Its content has a line for the email address and a password. They are different than the login details for your cPanel.
Type in your email address. Then enter your WHMCS Password. Now click on Login. That's all. You are at this point logged in to WHMCS and can begin to manage your hosting services, invoices, payment information, plus much more.
If you are set up, then click on the Logout Link in the upper right corner. You are now logged out of the account. There is a Click here to Continue link. Click on that link. That will bring you to the Portal Home.
This is the end of the guideline. You now know how to sign in to WHMCS.