Now if you've done the main guitar part, then this will be a doddle. This is the second guitar in the song and takes the rhythm role.
The song is in C minor and the rhythm guitar mostly cycles through C5 Ab5 and G5 Chords. These are nearly always played with nice easy downstrokes, and the chord changes are just positional so you should be able to follow them without too much trouble.
The rhythm guitar doesn't enter until the end of the intro riff. You should be familiar with the intro riff after the last guitar part, but if not, you can see it here too because the rhythm guitar does it too during the second solo. You can see it here. Just follow the picking directions and get the riff down slowly first. It repeats regularly (from after the second slide) and with practice you'll get the speed up in no time.
The rest is simply working through the C5, Ab5 and G5 powerchords! Simple :)
Just notice that we use the thumb to mute out the low E string whilst playing most of the C5 chords. Like here. This is just a sure way of avoiding strumming that low E string in case of over-strikes. You don't need to do it, but it will make things easier in the long run!