You are in your Client Billing Area. At the "You are here" line at the top of the page, you need to click on the Portal Home link, which will take you to that page. About half-way down, on the right hand side is a link called Order. Click on this Link.
This takes you to a page where you can Browse Products & Services. On the Menu Bar, click on the Register Domain link.
You will be taken to a new page called Register a Domain Name. In the blank box, enter the domain name you would like to register. Choose the top level domain (TLD) you would like from the drop-down box at the end of the line, whether it is .com, .net, .org, or something else. Then click on the Check Availability button below the box. If the name is available, it will be listed in a box below, called Choose Domains. Sometimes, more than one (TLD) is available, and you may have a choice. Choose the one you want, and click on the Add To Cart button. The next screen will allow you to make any add-ons to your domain that you wish, such as adding a hosting package. Click Update Cart to move to the next screen.
You are now at your shopping cart. After you verify all the information is correct, click on the Checkout Button. On the next screen, you need to scroll down and choose your payment method. Add any notes, or additional information you want to include with your order, and click the Complete Order button at the bottom of the page.
An invoice will be generated with all the information for the domain you just registered. Click on the Back to The Client Billing Area at the bottom of the page. Now click on the Client Billing Area in the You are Here menu.