in your camera? I mean like if you are inside and there is nothing but florescent lights and you have no flash... do you change your camera to florescent settings or fix it post processing? what if you DO have flash and are in a situation that calls for it combined with the florescents?
I use presets. It saves me time in post.
Combining flash with fluorescent lights, or any light of a different temperature than the flash for that matter, requires the use of gels. And then life can become tricky with fluorescents, given that they shift colour throughout each cycle (60Hz here, 50Hz in Australia, Europe, or any other part of the world where AC power is output at 50Hz). And that means you're pretty limited, in having to use either 1/30, 1/60, or 1/125 to avoid shifts. Start going faster than that and WB between frames can get really funky (and no AWB won't save you in such an instance; not if you're using flash).
I suggest you read-up on Strobist's Lighting 101.