Sony PCG-XG18 Primary User Manual page 43

If another device is in the multipurpose bay, remove the device. See
"To remove the floppy disk drive" on page 32 or "To remove the
second battery pack" on page 45.
Insert the floppy disk drive into the multipurpose bay with the VAIO
logo facing up. Continue pushing the drive into the bay until the
RELEASE lever locks into place.
Hold the diskette with the label side facing up.
Gently push the diskette into the drive until it clicks into place.
When you finish using the diskette, wait until the LED indicator
turns off and then press the Eject button to remove the diskette.