Step 1.
Make pre-snap read (i.e., does defense have 11 men on field? defensive formation, cover scheme, blitz pkg unimportant)
If Yes: Call play. Go to step 2 to decide which play
If No: Wait until they do (call timeout as required)
Step 2.
Check distance to 1st down (known as "X").
If X>0 but <2 call run (preferably to Foster)
If X>2 but <8 call pass (preferably to A.J.)
If X>8 Run draw play
Here's a photo of Matt informing his guys that they are now on step two .
Here's a picture of Matt getting the taser helmet activated for calling an audible .