How do I downgrade from 6.0 to 5.1.1

I don't understand anything anymore. I have an iPod Touch 4g with an ios 6.0 I'm using redsn0w to downgrade it, but it doesnt make any sense: -I enter to Extras>Even more>Restore> and enter my already downloaded 5.1.1 ios, and it says I have to enter in Dfu mode -I enter in Dfu mode -loading -"error: It was found in dfu mode instead of restore mode" -what -I enter in restore mode -I cant, it has to be in Dfu mode -try entering in Pwned dfu mode -"wrong dfu mode" What the hell am I supposed to do?!