(-1-2) -4 +4 -3 (+2+3)
You can change the sound by bending the same notes and using some hand wah-wah to create a real blues sound.

Try adding this bit at the end. Make a "ta ta, ta ta" sound with your tongue.
(+2+3) (+2+3) (+2+3) (+2+3)
When Steve slows this riff down some of the chords turn into single notes.