Install the floppy drive in the appropriate bay. It has its own shape power connector, smaller than those for the HD/CD, and which only fits one way. The motherboard comes with a ribbon cable to connect the floppy to the board. Pin 1 is labelled on the drive and the board, plus a red stripe runs down the pin 1 side of the ribbon. Ignore the middle connector. In the photo you can also see the twist in the ribbon. Keep the drives slightly out of the bays until all connections are made (e.g. you might find the cable is too short), then slide in and screw in securely. 4 screws is probably enough.