6 volt battery
I believe that what Chris wants to do is to connect six, 6V batteries in a manner to get 12V out of the bank. If so, the answer is to go to series/parallel. That means that you connect pairs of batteries in series to effectively make them into three very large 12V batteries. Then you would connect the three pairs in parallel with each other.
The pairs are connected with neg. to positive, then each pair is pos. to pos. and neg. to neg. When you finsih, just to be sure you have done it right measure with your meter across the terminals where you plan to connect the load. It should measure 12V-dc.