There are a couple of ways to play the main riff :
     D5 G5  F5 D5  D5  G5   F5 D5
E|-------------------|-------------------|
B|-------------------|-------------------|
G|---7-12---10-7---7-|-12---10-7---------|
D|---7-12---10-7---7-|-12---10-7---------|
A|---5-10---8--5---5-|-10---8--5---------|
E|-------------------|-------------------|

or

E|----------------------|-------------------|
B|----------------------|-------------------|
G|------12---10---------|-12---10-----------|
D|---12-12---10-12---12-|-12---10-12--------|
A|---12-10---8--12---12-|-10---8--12--------|
E|---10---------10---10-|---------10--------|


[Chords]
D5: x-5 -7 -7 -x-x  or  10-12-12-x-x-x
F5: x-8 -10-10-x-x
G5: x-10-12-12-x-x  or  3-5-5-x-x-x
A5: x-12-14-14-x-x  or  5-7-7-x-x-x


[Intro]
D5
(followed by main riff)  x4


[Verse 1]
         D5       G5              D5               (riff)
Well, if you ever plan to motor west
       G5                                  D5      (riff)
Travel my way, take the highway that's the best
         A5       G5      D5                       (riff)
Get your kicks on Route 66

         D5         G5          D5                 (riff)
Well, it winds from Chicago to A 
          G5                         D5            (riff)
More than two thousand miles all the way
         A5       G5      D5                       (riff)
Get your kicks on Route 66


[Bridge]
         D5                 D5
Well, it goes to St. Louis, down to Missouri
D5       D5         D5  D5 D5
Oklahoma City looks so, so pretty
       G5            D5
You'll see Amarillo, Gallup, New Mexico
A5                  G5
Flagstaff, Arizona, don't forget Wynonna
D5
Kingman, Barstow, San Bernardino


[Chorus]
   D5      G5                   D5             (riff)
If you get hip to this kind of tip
        G5                   D5                (riff)
And go take that California trip
         A5       G5      D5                   (riff)
Get your kicks on Route 66


[Interlude] (all x4, flute arranged for guitar)
   Dm                              Fm
E|-9---------------|-------------|-12----------------|-------------|
B|---10-------9-10-|-------------|----13-------12-13-|-------------|
G|-----------------|-------------|-------------------|-------------|
D|-----------------|-------------|-------------------|-------------|
A|-----------------|-------------|-------------------|-------------|
E|-----------------|-------------|-------------------|-------------|

   Bb                                Ab
E|-------------20-19-|-------------|-------------20-19-|-------------|
B|-18----------------|-------------|-18----------------|-------------|
G|----16-------------|-------------|----16-------------|-------------|
D|-------------------|-------------|-------------------|-------------|
A|-------------------|-------------|-------------------|-------------|
E|-------------------|-------------|-------------------|-------------|


[Bridge]
         D5                 D5
Well, it goes to St. Louis, down to Missouri
D5       D5         D5  D5 D5
Oklahoma City looks so, so pretty
       G5            D5
You'll see Amarillo, Gallup, New Mexico
A5                  G5
Flagstaff, Arizona, don't forget Wynonna
D5
Kingman, Barstow, San Bernardino


[Chorus]
   D5      G5                   D5             (riff)
If you get hip to this kind of tip
        G5                   D5                (riff)
And go take that California trip
         A5       G5      D5                   (riff)
Get your kicks on Route 66


[Outro]
         A5       G5      D5                   (riff)
Get your kicks on Route 66