I see people doing this type of chest workout:

3 sets of bench press
3 sets of flat dumbbell press
3 sets of Smith machine bench press
3 sets of machine flat press

The problem? It's all the same thing! Well, almost. But you are working essentially the same muscle groups using the same angle and pattern. It's redundant.

Not only that, 6 of your 12 sets use inferior exercises. Those 6 sets are what I call "garbage sets." You'd be much better off selecting exercises working different angles or portions of the movement instead of redundant exercises. Here's a better plan that avoids this common mistake.

Day 1: Back and Deadlift

Exercise 1:  Deadlift variation
Exercise 2:  Horizontal row variation
Exercise 3:  Vertical row variation
Exercise 4:  Scapula elevation (shrug, high pull) variation

Day 2: Chest and Shoulders

Exercise 1:  Flat bench press variation
Exercise 2:  Incline press variation
Exercise 3:  Overhead press variation
Exercise 4:  Lateral/front raise variation

Day 3: OFF

Day 4: Biceps and Triceps

Exercise 1.1:  Neutral (hammer) grip curl variation
Exercise 1.2:  Close-grip press variation
Exercise 2.1:  Supinated grip curl variation
Exercise 2.2:  Free weight triceps extension variation
Exercise 3.1:  Pronated grip curl variation
Exercise 3.2:  Cable/pulley triceps extension variation

Day 5: Legs

Exercise 1:  Squat variation
Exercise 2:  Unilateral (one-legged) movement variation
Exercise 3:  Hip extension variation (Romanian deadlift, good morning, etc.)
Exercise 4.1:  Leg extension variation
Exercise 4.2:  Leg flexion/curl variation
Exercise 5 (optional):  Calf exercise

Day 6: Chest and Back

Exercise 1.1:  Chest press variation (flat, decline or incline)
Exercise 1.2:  Horizontal row variation (cable/pulley)
Exercise 2.1:  Dumbbell flye variation
Exercise 2.2:  Rear delt exercise (rear delt raise, reverse pec deck, etc.)
Exercise 3.1:  Machine or cable/pulley pec isolation exercise
Exercise 3.2:  Scapula elevation variation

Day 7: OFF

If your goal is to get bigger and look better, the program above will work great if you make the right choices and train hard.

Related:  6 Ways to Reach Your Genetic Potential

Related:  Growth Factor Chest Training