FYI McNaught is moving rapidly Southwards so we've had our best shot at it from the Northern hemisphere - For those in/heading for the Southern Hemisphere it may continue to brighten and become even more spectacular over the next few days.
If you are V carefull the coma ( the round bit at the front) it is visible in daylight, but it's best to "hide" from direct sunlight by getting just into the shadow of a building or similar and looking about 5 degrees to the East of the Sun..