Grasp band with arms bent and palms facing out. Bend over slightly at the hips and push the band down laterally away from your body in a semi-circular arch while keeping your upper arms still.
Tips:
Puff your chest out to isolate triceps.
Experiment by pushing the band down at different angles from your body.
If you feel pain in your shoulders, bring your elbows more toward the front of your torso.