You put your arms in front of yourself as if you're holding a wheel. Holding it close will brake or reverse, holding it further in front of you will accelerate. You steer by rotating your hands as with a normal wheel.
You need vjoy: http://vjoystick.sourceforge.net
vJoy is a virtual joystick, your kinect movement will be translated in to a virtual joystick that can be used in video games. The gestures will be translated to JoyStick input over the X and Y axis.
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Future Features:
- Translate kinect movement in button presses
- Simulate to be a gamepad (xbox controller)