5-6 sets on flat bench.. then incline or decline bench for 3 sets. then I do either the smith machine or free weights 3 sets. then i do another pushing machine for 3 sets. (i mix up the middle part to throw my body off) then I work my triceps for a few sets while alternating 25 X 4 pushups.
takes about 70 minutes to complete this workout but it has worked wonders, my shirts don't fit anymore. not for noobs though.
For me, once a week (or more like every 6 days).... 3-4 sets flat bench, 2-3 sets incline, 3-4 sets pec deck (seat height changed every set), sometimes a couple sets dumbell flys.
I have plenty of room for improvement yet, (not really happy with size or shape of pecs), so I keep changing up the routine every few months.
Today I hit bench for about 7 sets increasing weight each set ten did about 4 sets heavy dumbbell press. Not my usual but it's usually several sets on each exercise. Never more than 3 different exercises.
4 sets of barbell flat bench
4 sets of barbell incline bench
4 sets of dumbbell medium incline bench
4 sets of dumbbell flat bench, palms in (sort of press fly).
Always finish with 4 sets of pushups with feet up on bar on the topmost position of bench.
Key is full range of motion with squeeze at the end never quite locking out. Chest good and sore for days.
I do chest once a week, except every third week I'll hit it twice. Just because I have a 3 way split working out 4 times a week.
On the norm, I'll do;
Flat bb bench 3 x 4-8
Db incline bench 3 x 5-10
Dips 3 x 10-12
Db flys 3 x 10-12
If I'm feeling it I might add another set or two
This is excluding my warm up sets they I do before my flat bench press. Every set I hit failure also. This has worked well for me personally. I weigh about 190-195 and I'm decently lean. I can put up 250 for 5 reps