1- Stand up straight facing a low pulley cable stand, knees slightly bent.
2- Grab the single low pulley handle with underhand grip (palm facing upward, thumb away) at shoulder width, arm straight.
3- Exhale and curl the handle up toward your shoulders by bending the elbows.
4- Inhale at the end of the movement, and lower the handle to the starting position, repeat until you finish your reps, and do the same with the other arm.
Tips and Advices:
1- The upper arm should always remain stationary next to your body and only the forearms should move.
2- Keep your back straight though out the exercise.
3- Don't allow your elbows to come forward in order to lift the weight.
Variation:
1- Overhead Cable Curl
2- Biceps Cable Curl