From the above menu click on Domains.
Search in the search bar to make sure the domain you want is available, if so then sign up for an account on the website.
After signing up, fill up the form and attach the necessary documents.
You will have to wait for the administrator to approve your email and phone number.
The payment process will take up to 24 hours to be approved in case of these domains (com.sa, .sa, net.sa, .pub.sa ). On the other hand the following domains will require approval from the Saudi network information centre (shc.sa, .med.sa, .org.sa, .edu.sa).