This tune has its roots in the Muddy Waters classic "Rolling Stone Blues," or as Jimi Hendrix called it "Catfish Blues"—a tune I showed you in Essentials: Blues Rock Grooves Vol. 1 (which I'm sure you have, if you don't, run do not walk to your computer to get your very own copy).
We start off the tune with an open position E minor pentatonic scale riff taking full advantage of the open strings, which I actually find to be the most difficult part of the tune. Pay close attention to the drum groove on this, as it really solidifies the backbeat when you're trying to sit in the groove properly.
I also can't stress highly enough to move your body! If you're not feeling the groove internally by tapping your foot, bobbing your head, swaying back-and-forth, etc. it will not come out in your playing. Just watch any video of James Brown!