Probably the best overall exercise you can do for your chest and overall upper body is the bench press. The primary muscles used in this exercise are the upper, mid, and lower pectorals. Secondary muscles used are the front delts, traps, triceps, upper and lower back.
To perform the bench press you need to position yourself correctly on the bench. Your butt and shoulders should be firmly planted on the bench. From your butt to your shoulders your back should be comfortably arched.
Your feet should be planted on the floor. This is where you will drive will start from in the exercise.
Next place your hands on the bar a little wider than shoulder width apart. Grip the bar as tight as you can and remove the weight from the rack and lower it down at a steady pace, making sure not to go too slow or too fast. Lower the weight just to the bottom of your sternum going down as close as possible without touching. Explode the weight back up to the starting position and repeat the process.