Character Discovery
Creating a Traveller in our game, and in Traveller overall, is not like most other RPGs where the Player comes up with a concept, rolls some dice, and then builds a character to meet that expectation. For our game the Player does start by rolling some dice, but then they continue to roll dice as their Travellers {Characters} life unfolds randomly. These rolls detail what a Traveller's life prior to starting play.
We call bringing a new player into our game Stepping Stone I.
The player rolls 2d6 six times and assigns those numbers to the six stats for their Traveller. They then pick which Career they would like to attempt to start and start rolling on the charts to discover what the Traveller did with their life during each of those four year terms. Once they have wound their way through the charts and come to the end of their career the Traveller takes stock of what they know, what they own, who they know, and then head off into the campaign. What we call Stepping Stone III.
One more way that this is Character Discovery instead of Creation is that we cooperatively look for reasons to tie each Traveller's life to at least of of the existing Travellers in the campaign. Discovering these these linkages exist often leads to more stories and a richer experience for everyone. A new Traveller might enter our game after months or years have passed on the calendar. We discover that the existing Travellers had interacted with this new Traveller while visiting a system and are now building a more complete relationship.