You can to access to certain Deepweb marketplaces with the only help of URL, which suggests the following : inpending clients and vendors lack the ability to enroll until they will obtain an URLs from an previously signed in customer.
Those can be found at http://deeponionmarkets.com/, it possesses active URL to suggested Darknet markets. You shall follow these URL in order to register on the sites.
Whenever there are some issues with an access,for example, links won’t work, you should hang around and check for Deepweb marketplaces link. Keep trying, as few markets shut down and open registrations periodically, due to server load.