Sit on seat with chest at height of handles. Grasp handles with shoulder width or slightly narrower overhand grip, just against sides of chest; elbows somewhat down to sides.
Press lever until arms are extended. Return weight until forearm is against upper arm. Repeat.
If lever arms freely move together or apart, keep moderately close grip throughout movement. Triceps will not be as involved in movement if grip is lower than chest. Seat height should be adjusted so bar is at least lower chest height. Also Lever Parallel Grip Bench Press for chest.