Join Taz Tally for an in-depth discussion in this video Using the exercise files, part of Photoshop Color Correction: Extreme Color Cast.
If you are a premium member of lynda.com, you have access to the exercise files used throughout this title. You'll want to download those exercise files and place them on your Desktop for easy access. Then all you need to do is double-click on that folder to open it, and look inside to see the files. Notice, in this particular project, you've got multiple starting files. The first one is this. Shark working start, and then you'll make that correction and then use this as your next starting file, to work with the clown anemone file. And it's just that easy. If you are not a premium subscriber to lynda.com, you don't have access to the exercise files, but you can follow along from scratch with your own assets.
Check out the first installment in this series, Photoshop Color Correction: Fundamentals, for more detailed information about adjusting color in Photoshop.