In this section, we have a strong rhythm mixing octave chords with palm-muted alternate picking in between.
As always with octave chords, make sure that your index finger mutes all 4 of the non-applicable strings. We only want the A and G strings to sound, so your index finger needs to slightly touch the other 4 strings so they're muted.
If you observe the tab closely, you can see how none of the octave chords are palm muted. But on the other hand, all of the notes between the octave chords are palm-muted. Make sure to keep that consistent with your picking hand. Strum the octave chords normally, then once those Low E string notes come in, let your picking hand's palm immediately fall on the strings to palm mute.
Lastly, be sure to mind your octave chords when you're doing those quick slides. Make sure the notes have proper sustain and don't die out on your way to the next chord.