At this point you have three options for the use of the supply outputs. First, if your load is at or less than the 12 volt maximum rating you may connect your equipment to the black and yellow leads supplying the voltage to the four pin Molex-type connectors coming from the supply. For higher power equipment, parallel several or all of the black leads together and do the same with the yellow leads to minimize your voltage drops. Connect your load to these new junctions. All wires of the same color are the same voltage.
All black wires are common ground or reference point for all voltages.
There is a long cable coming from the supply containing about twelve wires. This may be used as a source of your power. The color codes remain the same. This will reduce the output voltage to 14.3 or 13.6 VDC respectively. It will also provide isolation between the supplies and any standby batteries you may have in your system.