you play the above riff untill she stats singing the verse and there is no guitar there
when
after that is the chorus with no guitar then u play the begining riff again then this again
and then this before the harmonica
then this over the harmonica part as many times as needed
then this at the end play this 6 times at the end and fade a lil bit on the last three times
keep makin it softer each time till can barely be heard if you have a volume pedal use