The setup for this shot is extremely simple; you don't even need the cue ball. All three balls go on the headstring. Set the 3 ball along the first diamond on the left (assuming you're also shooting to the left), the 2 ball on the head spot, and the 1 ball on the diamond on the right.

Nothing fancy about shooting this shot either. It helps if the table rolls straight though. First figure out the speed you need to make the 3 ball just fall in the pocket. You can even purposely skim it off the long rail to give yourself a little more room. Hit the 2 ball with medium speed and then you can whack the 1 ball with all your might.