STARTING POSITION:
Select the appropriate plates amount to put them on the bar of a Smith machine You need to place a bench next to the smith machine to do the exercise. The bar of the smith machine should be at your shin height. Place the right leg on top of the end of the bench and your right hand on the other end of the bench for support. Your upper body should be parallel to the floor. Contract your pelvic floor and core while keeping your chest facing the floor. Grab the bar with your left hand using a neutral grip (palm of the hand toward your torso).
MOVEMENT:
Retracting the shoulder blade, pull the bar up to the side of your chest while you exhale. While your are doing the exercise, move only the arm, make sure you don't move any other part of your body. Return to the starting position in a smooth movement while you inhale. Repeat the movement for the specified amount of repetitions and then switch sides and repeat with the other arm.
TIPS: The exercise key is quality over quantity. The trick is to perform the exercise using proper form. Make sure you do all the repetitions in all the range of motion of the exercise.