Standard tuning
Note: your hand doesn't change position in the intro shown below. 
your ring finger is alwasy on the 5 fret A string.
You use your pointer finger for the F note (which you bend a little and vribrate when you hammer down on it)
Use your pinky to hit G note. 
E|-------------------------|
B|-------------------------|
G|-------------------------|
D|-3bv-0-3bv-0-3-0-5-3-0-3-|
A|-5---5-5---5-5-5-5-5-5-5-|
E|-------------------------|
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 | bv   A slight bend then vibrato. (hold the bend)
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