You'll need a vendor account. At the moment vendor registration is closed, it was open for a short period today for 25 people but those spots got filled. It should reopen again soon, when you register to become a vendor you'll need to pay a $500 refundable bond which you get back after a certain amount of sales. Any updates on vendor registration will be posted here, - http://silkroad5v7dywlc.onion/index.php?topic=4658.0 While you're waiting you should research PGP encryption and how to ship packages safely etc.