Extremly easy. Chuse the buttonpossition that suits you, give it a name and what colors you like then click "New entry" cycle through to AmigaDOS and type "MOUNT CD0:" next to it.
the "AmigaDOS" selection acts like a shell, if nothing else is selected you won't get any output witch is perfectly fine for this operation but others you might want to see what happens and then you have the put a checkmark next to the "Output to window" flag... combine it with a Close delay so you get to see the information (-1 will delay indefinitly until left mousebutton is pressed).
