When performing a ascending pyramid chest routine, you should start with light weight and ascend to heavy weight. Your first set should be warm up reps.
Ascending chest pyramid workout
-Bench press (Barbell) 4 x 15(warm up), 12, 10, 8, 4
-Incline bench press (Dumbbell): 4 x 15(warm up), 12, 10, 8, 4
-Standing flies (Cable): 4 x 15(warm up), 12, 10, 8, 6