Please see these instructions at the main Web site:
http://counterparty.io/get-started/#create-token
You can also refer to this video below for additional details.
Other approaches
-
Use
counterparty-cli
or Counterparty API. -
Use a 3rd party service that not only provides a user friendly interface (Please note that those are 3rd party services run by their respective owners and that Counterparty cannot accept responsibility for their use).