Cool dark tune. It's mellow for Slipknot but you can play it on the acoustic. She's tuned down 3 semi-tones or 1 and half steps. I got a couple lyrics wrong but it was my first take so I stayed with it. The tabs I used are from http://www.ultimate-guitar.com/tabs/s/slipknot/snuff_crd.htm
The trick is to tune the whole guitar down 1 1/2 steps or 3 semitones. Most electric tuners have a "Flat" option, just press her three times and detune and its simple, only 4 chords. I ignor the A5,B5,C5,E5,F5 at the end of the tab and just play through.
Cheers
Here's the tuning of the guitar 3 semi tones down:
C#,F#,B,E,G#,C#