If you live in the Southern Hemisphere, Comet McNaught is currently hard to miss if you face southwest shortly after sunset. But if the comet becomes any fainter, you can use the chart at right to locate it.
Things aren't completely hopeless for northerners, either. The comet's tail is so huge that it's far end was spotted from pristine dark sites in the Northern Hemisphere days after the head disappeared. See the January 18th and 19th pages of spaceweather.com for details.