Instructions
Plug in your Nyko controller into a free USB port on your computer.
Launch Dolphin emulator from your desktop.
Click "GCPad" on the Dolphin tool bar.
Click "Device" drop-down list and then click your Nyko game controller.
Configure your Nyko game controller. You can configure the face buttons, C-stick, D-pad, Main stick and the triggers in this section. For Example, press a button such as "A" in the "Buttons" column and then press a button on your Nyko game controller to configure. You only have a few seconds to configure a button before you have to restart the process over again.
Click "Save" to save the configuration. This configuration is the default configuration when you play a game on the Dolphin emulator.