iMAX B6 charger question

I bought the iMAX B6 charger and the charger 2 pack 3 cell special cable (a cable to make use of the 6 cell port to charge 2 packs of 3 cell battery at the same time). In the manual, it says to connect the balanced charge cable and the +ve and -ve cable to the charger at the same time.

Question is how to connect the 2 packs of 3 cell battery using the special cable and connect +ve and -ve cable of the two batteries at the same time? Thanks.