Usually, people had to either figure these concepts out by themselves or, in most cases, refer to the beast whose bloodline they had used.
In my case, I didn't have much of a problem figuring out my concept. My ability to summon the dead, plus my family history of affinities, made it obvious. My concept was 'Death.'
Now, if I had followed the norm myself, than I would have had to spend several months resonating myself with the concept of Death as well. But fortunately or unfortunately I had spent the last few months travelling through the Wastes.
During my travels, I had faced one life-threatening situation after another, fighting against harrowing enemies one by one. In almost all of my encounters, I either faced death or ended up killing my enemy instead.