Stand on your resistance band, feet are about hip width apart. Bend your knees slightly, move your straight back foward. The movement should be done from your hips, not from your back. Grab the band, move your shoulders back and down and create tension. Row your arms back by bringing your wrists towards your rips. Shoulders stay down, elbows remain close to your side body, abs are engaged. Isolate the movement to your arms and try not to move your lower body.
Exercises
Butterfly with Thera Band
Bring your resistance band under tension behind your shoulders. Arms are stretched to the sides. Bring your straight arms together in front of your chest.