When playing this contest , when I explain the particulars
of the game , my opponent will balk at the idea of
turning out the lights . " Impossible " they say" to  mark
something accurately without being able to see it ."
Then I say  “OK , what if I leave the lights On for you ,
and I wear a blindfold ?”
This seems agreeable to them . They then perceive
that condition as one that gives them the advantage .
The advantage I have is setting the divisions of the
layout ( Thirds and Halves ) . The blindfold will make
no difference to me .  Considering that you will now
be able to ’ see ’ what you are marking , What layout
tool(s) would you bring ? …and how much time will
it take you ?
 three equal divisions on the face .
  divided in half on the edge .