That's the easy partThere really only is a few unique cables.
Sata - flat thin black connectors (used for hard drives and optical drives)
Molex - white 4 pin chunky connector (used for the above +fans, pumps, cathodes... and anything else really)
24 pin (into mobo)
4+4 [8 pin] (into mobo to power CPU)
6+2 [8 pin] (for graphics cards) *will be labelled PCI-E*
That's pretty much all that comes off of a PSU that is essential and that's what they're all for.
The hard part is keeping the cables out the way of everything else and keeping it tidy for optimum airflow/coolness.
For the graphics card, with the 2 pin cable can that just go anywhere seeing as there is no slot on my PSU for just 2 pins?
Yep.
Nice!

There really only is a few unique cables.
Sometimes walking away and coming back to it helps.. ^_^ Now everything is done!
Just staring at my computer isnt very fun!