Set the pins so that the bar rests on them a few inches above the chest. Press and hold the lockout for at least one second to take advantage of the peak contraction and then lower under control. Rest the bar on the pins for just a second before performing another rep.
Do 2 sets of 6-8 reps after your warm-up sets, leaving a rep or two in the tank on each set. Take 2-3 minutes of rest between sets.