Apple: Show Hidden Files in Mac OS X

To enable hidden files/folders in finder windows:
1. Open Finder
2. Open the Utilities folder
3. Open a terminal window
4. Copy and paste the following line in:
        defaults write com.apple.Finder AppleShowAllFiles YES
5. Press return
6. Now copy and paste the following line into the terminal window:
        killall Finder
7. Press return

You should find you will now be able to see any hidden files or folders. One you are done, perform the steps above however, replace the terminal command in step 4 with:
defaults write com.apple.Finder AppleShowAllFiles NO

If the above is not working for you, you may want to try switching YES/NO to TRUE/FALSE .. Beware that this is case sensitive!
defaults write com.apple.Finder AppleShowAllFiles TRUE

Reference:

Show hidden files Mac OS X 10.7, 10.8 and 10.9 Mavericks

http://www.mikesel.info/show-hidden-files-mac-os-x-10-7-lion/