This is the pattern you can use to accompany the Blues in G. The root note is G, and the
other G notes are coloured red. The "blue" notes are coloured blue, and the rest of the notes
in the pattern are black. If you know the key is G, just play these notes. If the key is A,
move everything up 2 frets. Any key can be played just by sliding this pattern up and down
the neck. If you don't know the key of a piece you are hearing, slide your finger up and down
the low or high E strings (1 and 6 strings) until you can match the note to the tune.
Experiment with Position 1 until you are somewhat comfortable with it. Then move on to the
other positions. Above all, have fun!