This tutorial provides the steps required for connecting a Apple Wireless keyboard with Mac Book Pro via Bluetooth. Before connecting the Apple Wireless keyboard, make sure it is turned on. Then click the Apple icon on Mac Book Pro and select System Preferences from the menu list.
In the System Preferences window, click the Keyboard option under Hardware section.
In the Keyboard Preferences, click the Setup Up Bluetooth Keyboard button.
This would start searching for Apple Wireless keyboard and once found the continue button will be enabled.
Click the Continue button to pair the device by typing the passkey on the keyboard then press the Return key.
By this way you can setup a apple wireless keyboard to Mac Book Pro through Bluetooth.