There are two broad paths to register for Amazon Easy Ship once you are a registered seller on Amazon.
Most sellers are enrolled automatically during registration if you have an address within Saudi Arabia. Otherwise, if you registered as a self-ship seller (perhaps because you provided an address outside of Saudi Arabia) but are able to fulfill orders from a location within the country, you can visit the Easy Ship Settings page in Seller Central to enroll in Amazon Easy Ship.
Once you are enrolled in the program, all your eligible orders will be delivered through Amazon Easy Ship. You will have to schedule the package pickups within Seller Central and prepare the package for the delivery associate before the allotted pickup window begins. See Managing Amazon Easy Ship Orders help page for more information. You will not be allowed to sell or ship products that are restricted from the Amazon Easy Ship program.
Follow the links at the bottom of this page for more specific steps on another way to check your eligibility and register for Amazon Easy Ship.