Follow these steps to connect the first disk drive to your Apple IIGS:
1. Make sure the computer is plugged in and its power is switched off.
Connecting a drive when the power is on, or within 30 seconds of switching off the power, could seriously damage your disk drive and your computer.
2. Connect the disk drive cable to the disk drive port on the back panel of the Apple IIGS and tighten the thumbscrews.
Connecting disk drives