Sit in a chair with a table to your side.
Place your weaker arm onto the table with your elbow bent, and allow your hand to rest over the edge of the table.
Take one end of the resistance band in your hand, and hold the other end in your other hand.
Take up the tension in the band, then lift your wrist up as far as you can, keeping your forearm in contact with the table.
Hold this position before slowly lowering it back down.
Aim to keep your elbow, shoulder and body still during the exercise.