Using Dumbbells on a incline bench

With a comfortable working weight 

Lying face up on the bench while holding the dumbbells palms facing toward you 

Safely with your arms slightly bent with a flying motion slowly move downward toward the floor without hyper-extending the elbow

Once you have reached maxed tension slowly move back up to max tension to complete your repetition

Try not to let your chest relax too much throughout the ranges of motion 

After completion, repeat the process