This riff requires you to use a precise down, up, down, up motion with your strumming arm. On the downbeat we mute the strings for a percussive sound and on the upbeat we strum the chord fragments. It’s a little trick to get at first, but practice along with the jam track until you get it!
Here’s what the riff sounds like with guitar and bass:
The bass guitar steals the show here. In the 2nd and 4th measures staccato notes are played on the 5th fret. In the music notation you can see the staccato sign. The notes with a little dot above is called a staccato note. Staccato means “cut short crisply, detached”. The use of staccato is very important to the overall sound of the riff.