Kneel down on the floor and place your elbows and forearms flat on the bench. You should grab the dumbbells with your palms up. Make sure your wrists are just a touch past the edge of the bench. This is your starting position.
Lower both dumbbells at the same time and at the same rate. Curl your wrists down all the way as low as possible. Once at the bottom, curl your wrists back up as far as the natural range of motion allows you. Repeat entire movement for the desired or prescribed number of repetitions.
Perform this exercise in a smooth and fluid motion
Don't jerk the dumbbells up to fast
SPECIAL NOTES & LEVEL of DIFFICULTY VARIATIONS
To increase the level of difficulty, slow down the movement or use heavier dumbbells.
This is an exercise that is the variation of the Barbell Wrist Curl. It's a bit more difficult because it's done with dumbbells. We all know that with dumbbells you need to employ more muscles and the balancing aspect is also more difficult with them. This all translates into engaging more muscles and hence more muscle development.
This exercise is perfect for building big forearms. It has maximum impact and it can be done at home or the gym. Also, it's equally good for both beginners or advanced lifters. However, advanced lifters might need to use heavier dumbbells.