Learn some chords and practice changing them....if you're already doing that, look at the scales too. If you want a starting point, Schmange has a good section on scales posted on the trick section (Metallica like the pentatonic scale and thats a good one to start with) Make sure you practice slowly to begin with using the 'box shapes' and gradually work your way to learning it up and down the fretboard. Learn which chords you can play scales over (try the E pentatonic over E, A and B....thats a basic blues pattern.)
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