Watch the Giraldo's Jessie online guitar lesson by Angus Clark from Essentials: Radio Rock Solos
When the vamp is moving this quickly, it's almost like the rhythm section is just pedaling a D Major chord. You don't really need to “cut the changes” at all, except where it moves to the A chord at the end for the buildup. Be sure to hit that right on the money, 'cause it's the only harmonic variety that you have to work with.
First Lick: Thirds! If you can't play a descending D Major scale in thirds on the top two strings, now is the time to learn. Also note the rhythmic motif that's used to play this scale - it's that kind of thing that gives the listener something to hold onto.
Second Lick: This is a D Major pentatonic lick ending on the open string, so make sure to get those pull-offs clean and in time!
Third Lick: The great thing about using the open string in the last lick is that you can jump registers. This is one of those things that guitar players use across all genres. There are so many examples of classical guitar transcriptions where the open string is used to mask a position shift in the left hand, so take a page out of Segovia’s book while your ape-ing Neil Giraldo - you'll be glad you did.
Intervalics: In this case it's a 5th, played kind of like an ambulance siren. Not hard to do, but catchy as all get out.
Fourth Lick: This is some scaler material with a little motivic development, and a big payoff on the A chord with, you guessed it, a blues lick!