Drums come in first, then this riff
Intro Riff
e |----------------------------------------|
B |----------------------------------------|
G |----------------------------------------|
D |--5-5-5--7------------------------------|
A |------------5-5-5---7-7--7-7--7-7-------|  
D |----------------------------------------|

Main  Riff
e |----------------------------------------|
B |----------------------------------------|
G |----------------------------------------|
D |--5--5-5-5--7---------------------------|
A |---------------5--5-5-5---7-7--7-7--7-7-| 
D |----------------------------------------|

Riff 1 play this 2x on the 3rd time you here the main riff
e |----------------------------------------|
B |--11-----------11-----------------------|
G |-----11---12------11---9----------------|
D |----------------------------------------|
A |----------------------------------------|
D |----------------------------------------|

While Bobby is hitting away with his drums, slide down the D-string of
your guitar

Chorus Riff (this doesn't show strumming pattern)
e |----------------------------------------|
B |----------------------------------------|
G |----------------------------------------|
D |---5---0---2-----7---0---2--------------|    
A |---5---0---2-----7---0---2--------------|
D |---5---0---2-----7---0---2--------------|


Riff 2
e |------------------------------------19--|
B |--20--19--17--19--------20--19--17------|
G |-------------------16-------------------|
D |----------------------------------------|
A |----------------------------------------|
D |----------------------------------------|


Riff 3
e |----------------------------------------|
B |----------------------------------------|
G |----------------------------------------|
D |--------------------8----------8--------|
A |--6---4-------4-6-----9---4-6---9---6---|
D |----------8-----------------------------|

Riff progression
Drums
Intro Riff
Main Riff 6x - Insert Riff 1 on 3rd time
Drums
Chorus Riff 2x
Drums
Main Riff 8x
Chorus 2x
Main Riff 8x
Riff 2 2x
Drums
Main Riff 10x
Riff 3 2x (do main riff in he background)
Main Riff 4x
Drums
Chorus Riff - a couple of times to fade