The Dumbbell chest press works your pectoral muscles, anterior and lateral deltoids, triceps and rotator cuffs. Compared to a barbell Bench Press, this exercise has a greater range of motion and can help to correct muscle imbalances as one side of the body cannot compensate for the other in the same way that it can in a dumbbell bench press.
To begin with, set yourself up lying with your back on a bench. From here plant your feet firmly into the floor and lift your weights so that they are extended into the air with straight arms, stacking your wrists over your shoulders. From here, take your arms down with your elbows coming out at a 45 degree angle from the body, ensuring that your wrists stay vertically above your elbows.
You should aim to bring your elbows down as low as they go to achieve a stretch through the chest. To gain more power in the movement you can exhale as you push the weights up into the air.