Need Help With Imac G4 / Midi, Beginner needs basic midi setup help Options

[toolbc]

I have a brand new Imac G4 running OSX and a Yamaha Motif 6 workstation. It connects to my computer via USB, but I have no idea how to set it up to work with my Mac. I have tried messing with the Audio Midi program but have not installed the device properly, and it does not detect the device. Please give me any advice if you know how to set up a midi device on a new Mac. Thanks.