Ahhh a favorite of mine.
Reps. So Max 8s would be get 8 reps at a weight and add weigh next workout.
Hypothetically if you do max 8s you should start at your 10-15 rep max (65-75% of 1RM) and in that situation you have a couple options.
You could do 1 huge AMRAP (i do this on my uninspired days) OR you could do 8 rep sets until you fail to get 8 reps (when I want some extra puishment). For a 12-15 rep max that is probably around 3-4 sets of 8.
If you have any other questions I am here. Also I posted this in the other thread because I think it will be a common question.