Which part of your chest is the less dominate?
From what I've studied and learned so far (and referencing Frederick Delavier):
To accentuate the middle part of the pec, use exercises that bring the arms to the front and middle part of the body, i.e. flys or pec machines. The triceps don't get as much action, but you can target the inside better.
To accentuate more of the upper pec, the clavicular head, use an incline bench press, either dumbbells or bar.
To shape the sides, use a wider grip.
To hit the lower part, use a decline bench.
For my routines, I rotate through combinations of fly movements and presses, as well as superset pushups (again, either flat floor pushups, inclines or declines, or all three). You can really push the work with pushup supersets.
Hope this helps. If you need anything more specific, such as rep ranges, hit me up.