The 'short' version is: one goes online and fills out a couple of forms and sends their current title, a copy of your driver's license and a check to Clay County. In about a week... if one is in the US... you'll get the plates and registration directly from Clay County. They are FAST. The title which must come from the State... and they are not as quick... was taking 4-6 weeks for the last several years.
Then annually Clay County will send out a notice for renewal and a new 'year' sticker which one can pay by mail or online credit card. This is what makes the service nice since other states will not let you 1) have a title/plates if you don't live in their state, and 2) renew said by mail.