Alright all you one finger wonders out there, this one is for you! This is a fun kind of riff that you can really do pretty much anything you want with, once you get the hang of it.
The main idea is that you're using the open E string as a drone, and then you're hitting notes out of the scale on that same string. You can use this in different keys, only make sure that there's always an 'E' in the key you're working off.
Need more ideas? Try working off a different string. Try moving between strings, or if you're really up for it, try using one string as a drone and pull your notes off a different string.
Really, the sky is the limit, but this should get you started. Have fun.
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