Under Mac OSX, if you choose "Photoshop manages Colours" in the print dialogue, the OS automatically invokes Colorsync and automatically disables Color Management (unlike Windows where as I recall you can still set/overide that choice). You don't need to do any more in that regard.
But you need to ensure that you apply the appropriate paper profile in the print dialog, and the correct media setting for the paper you're using, in the print driver.
If you are doing all this,and the monitor profile is good, then I'd have thought the only(?) possible explanations for very bad matching would appear to be a bad printer profile, and/or an ink malfunction in the printer. Head clean?
(PS are you using Canon OEM inks? - if not you will need to build your own profile for the paper: Canon's canned profiles are built using, and assume, their own inks, obviously)
Tim