Apple iMac (21.5 and 27-inch, Late 2009) - Manual (Page 29)

Chapter 2 Life with Your iMac 29
To pair your wireless keyboard:
1 Press and release the On/off (®) button to turn on your wireless keyboard.
2 Choose Apple () > System Preferences, and then click Keyboard.
3 Click “Set Up Bluetooth Keyboard …” in the lower-right corner.
4 Select your wireless keyboard, and then follow the onscreen instructions.
If you don’t pair your keyboard with your iMac within 3 minutes, the indicator light and
keyboard turn off to preserve battery life. Press the On/off (®) button to turn your
keyboard on again, allowing you to pair it with your iMac. Once you successfully pair
your keyboard with your iMac, the indicator light glows steadily for 3 seconds, and
then turns off.
Using Your Keyboard
Customize your keyboard using Keyboard preferences. You can change the modifier
keys, assign keyboard shortcuts to menu commands in a Mac OS X application or in
the Finder, and more.
To customize your keyboard:
1 Choose Apple () > System Preferences.
2 Click Keyboard, and then click Keyboard or Keyboard Shortcuts.