this is a sad representation of a curl period. a true "preacher curl" begins with your triceps flat against the pad, and forearms perpendicular to the ground. you extend your arms slowly until straight and wrists down. you then curl the bar back towards yourself while maintaining position on your seat and keeping your chest from moving forward or backward to assist leverage at parallel to the ground. your forearms should return to perpendicular to the ground and 1 curl is completed. learn how to properly lift for two reasons, to lift safely so you don't hurt yourself, and to make your accomplishments legitimate and real.