This is a sample rubric I created sometime ago but regardless it has stood the test of time.
Deck Type 0/3 Tier 1-0 points, Tier 2-1 point, Tier 3-2 points, and other 3-points
Number of Cards in deck 0/3 (40-42 3 points)(43-44 2 points)(46-47 1 points)(48-60 0 points)
Extra Deck0/3 (as any deck can used xyz also provides more to a deck) (0 0 points) (1-5 1 point) (6-10 2 point) (11-15 1 point)
Misplays 0/100 -20 per misplays (include falsely playing a card or misinterpreting a card without asking what it actually means such as thinking the removal of grapha is an effect instead of a summoning procedure or summoning a monster in face up defense position without the card indicating to do so.)
Rulings 0/21 (test before hand of basic game play concepts such as when can mst be activated or what spell speed is a counter trap and what can be chained to them; if testie wishes for you to provide the answer via a link you must provide one.) 7 points per correctly answered question.
Duel Result 0/60 (Tester vs Testie) (2 v 0- 0 points) (2 v 1- 20 points) (1 v 2- 40 points) (0 v 2 - 60 points)
Now Some opinion is necessary as not all duels can be determined on the materials provided above.
Ability to control use their deck 0/10 (meaning the way they play their decks is filled with good ideas but it doesn't have to thwart their opponent)
Ability to overcome obstacles 0/10 (here is the ability to thwart opponent meaning clearing the field or negating effects and summons that could end game or do a massive amount of damage. aka: playing a trag or gorz against a very strong monster.)
Overall Score 0/210
(what dorm they got down here)
Exiled Exodia Dorm 0-119
Slayed Slifer Dorm 120-159
Ravage Ra Dorm 160-189
Obliterated Obelisk Dorm 190-209 (this allows one misplay or one bad hand as everyone is not perfect
The Creator God of Light, Horakhty Dorm 210