For the floppy cable, you must align the red stripe to pin 1 on the motherboard side and on the floppy drive itself. You have to look at the floppy PCB to find out which side pin 1 is on side it's not standardized.
The end with the twist goes to the floppy drive. The opposite end goes to the motherboard. The middel connector (if available) isn't used.
Some optical drives don't like being on a 80 wire IDE cable. If you have a 40 wire IDE cable available, use that and jumper the optical drives to master and slave.
Cricket