Stand up straight with your side to a wall, holding a resistance band in both hands.
Take your arm to be exercised out to your side and place your hand up against the wall.
Walk your fingers all the way up the wall as high as you can go against the resistance of the band.
Anchor the other end of the band firmly in your other hand.
Make sure your body does not rotate and you do not hunch your shoulders.
Control the movement as you walk your fingers back down to the starting position.