Adding percussive sounds to your guitar playing is a great way to spice up your playing! It gives the illusion that you are playing two parts at once. Maybe it’s not an illusion then!
As you will see, this technique is applied on beats two and four of a typical 4/4 phrased musical structure. Imagine if you will a basic rock or pop drum pattern where the kick drum plays on beat one and three while the snare drum is struck on beats two and four.