Cap'n Crunch

A while back, I explained how to use color correction gels to match your flash to the color temperature present in a room.

Another quick-and-dirty solution: flash caps.

Using your flash in a room with "tungsten" lights? These have a color temperature about 3200k, and your flash puts out light about 5500k. To match the two sources, use an gold or amber or yellow cap to "warm up" your flash, then set your white balance to "indoor" or "tungsten."

Using your flash in a room with overhead fluorescent lights? These are often 3800k, but with a greenish cast. Use a green cap to make your flash match the fluorescents, then set your white balance to "fluorescent."

That's kinda simple. It's effective, though.

Use the gels when you need precision -- when you just have to get the color perfect -- and the caps when "close enough, but fast" is the way to go.