They attached the two gold chains to the two rings at the ends of the breastpiece;

and two braided chains of pure gold, like a cord, and attach the chains to the settings.

the other two ends of the two chains you will attach to the two settings and then attach them to the shoulder pieces of the ephod at the front of it.

the other two ends of the two chains they attached to the two settings, and they attached them to the shoulder pieces of the ephod at the front of it.