Lie down on a flat bench and hold the dumbbells above your chest (aligned with your mid-chest) and your arms slightly bent. This is your starting position.
Lower the dumbbells down until your upper arms are parallel to the floor. Then, squeeze/lift the dumbbells back in to the original starting position. Do this movement for the desired number of repetitions.
Perform this exercise in a smooth and fluid motion
Don't lock out your arms at the top
Don't jerk the weight up
SPECIAL NOTES & LEVEL of DIFFICULTY VARIATIONS
To increase the level of difficulty, slow down the movement or increase the weight.
This exercise is one of the all-time classics that is excellent for your inner chest area. The key to getting the most out of this movement is not to rush it nor go too heavy. This exercise is not for building mass - rather it's a finesse exercise that helps build shape and gives separation to your chest muscles. It's perfect if you're on a fat burning and definition-enhancing workout regime. Doing this exercise for a few weeks will certainly "frame" your inner chest muscles and give you that superhero chisseled chest look!
Thus, take your time in setting up properly on the flat bench and then executing the movement accurately without rush.