This is an old gadget I've made to split some poser around.
The schema show how the power is split: 4 x 3pins connectors for fan or anything else needing 12V. power and 4 x 2pins connectors for led circuits needing 5V. power.
All you need is:
4x male 3 pins connectors
4x male 2 pins connectors
1x female 4pins molex.
1x soldering plate
Tools:
cutter for the wires
soldering iron
Perfect for wiring managment