Regardless of all the advice here about the number of reps, sets, times per week, best chest exercise, etc, you only need to know one thing to get a bigger chest, or really just get bigger overall: lift weights regularly.
Once you've actually commited yourself to lift weights, and do so regularly, then you need a workout schedule. Do X number of sets, Y number of reps per set, Z number of I type of exercise, and N number of workouts weekly. X, Y, Z and N are numbers that you think are reasonable. I type of exercise is the type of weight lifting movement you want to do or like to do. When you find that progress has stopped, change X, Y, Z, I, and/or N until progress comes again. Don't neglect to work your lower body. Don't neglect to work your lower body. And, don't neglect to work your lower body. Also, don't neglect to work your lower body. Eat lots of healthy food and repeat ad nauseum.
When you lift weights you're going to hear a billion different opinions on what works and what doesn't. Try them out if you're not making progress. But remember that they are only opinions, because you will quickly find out that what works for one does not work for another, especially when it comes to weight training. And don't bother trying to figure the absolute perfect routine, because asides from mental masturbation, it's pretty pointless.
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