[Deathstar 80]

Most importantly, you should get a defense based on the talent and size of your players.

Secondly, you are to see how your opponents are. Are they more of passing teams that are good against stopping the blitz? Then have good coverage. Do they mostly focus on running? Put four or five people on the defensive line.

Lastly, you are to chose a defense that's easy on your defenders. An example is that a cornerback for the Green Bay Packers was happy when he heard they were switching to a 3-4 defense. This is because he considers it easier to play in a zone defense (where he watches the quarterback) rather than a man to man defense (where he watches the receiver).

Personally, if I could chose any defense, I would chose the 4-3 defense. By controlling the line of scrimmage, you can stop the run and cause trouble for the quarterback.