I charted Madden's Playbook a long time ago and use that even today. I use my LAEFL Action Box which has 2D20 (different colors) in one compartment; 2D6 (different colors) in another and a single D6 in the last.

The 2D20 determine the Offensive Formation and the Defensive Play. The single D6 determines the strength of the O-formation: left (odd) or right (even). For O, I use 20 different formations with 20 different plays each, most plays are the same just different formations.

Defense, however, is based on the Offensive "package" i.e. they don't play a 4-3 if the Offense is in a 5WR!?! And I set the D in their play, rerolling if the play doesn't match the Down and Distance i.e. 3rd and 1, I'm not running a "Prevent!?!" Same for Offense, I'm not running Goalline if it's 1st and 10 from my own 20!?!

After Defense is "set", I'll reroll for the Offensive Play and run it just like it's drawn up. Not only does this keep both sides fair, but it allows me to see what REAL LIFE plays work in miniature!